uTools-Manuals/docs/python/2to3.html

<div class="body" role="main"><div class="section" id="to3-automated-python-2-to-3-code-translation"><h1><span class="yiyi-st" id="yiyi-10">26.7. </span><span class="yiyi-st" id="yiyi-11">2to3  - 自动Python 2到3代码翻译</span></h1><p><span class="yiyi-st" id="yiyi-12">2to3是一个Python程序，它读取Python 2.x源代码，并应用一系列<em>修复器</em>将其转换为有效的Python 3.x代码。</span><span class="yiyi-st" id="yiyi-13">标准库包含一组丰富的修复程序，它们将处理几乎所有的代码。</span><span class="yiyi-st" id="yiyi-14">2to3支持库<a class="reference internal" href="#module-lib2to3" title="lib2to3: the 2to3 library"><code class="xref py py-mod docutils literal"><span class="pre">lib2to3</span></code></a>是一个灵活的和通用的库，所以可以编写自己的修复软件2to3。</span><span class="yiyi-st" id="yiyi-15"><a class="reference internal" href="#module-lib2to3" title="lib2to3: the 2to3 library"><code class="xref py py-mod docutils literal"><span class="pre">lib2to3</span></code></a>也可以适用于需要自动编辑Python代码的自定义应用程序。</span></p><div class="section" id="using-2to3"><h2><span class="yiyi-st" id="yiyi-16">26.7.1. </span><span class="yiyi-st" id="yiyi-17">使用2to3 </span></h2><p><span class="yiyi-st" id="yiyi-18">2to3通常会安装Python解释器作为脚本。</span><span class="yiyi-st" id="yiyi-19">它也位于Python根目录的<code class="file docutils literal"><span class="pre">Tools/scripts</span></code>目录中。</span></p><p><span class="yiyi-st" id="yiyi-20">2to3的基本参数是要转换的文件或目录的列表。</span><span class="yiyi-st" id="yiyi-21">递归遍历Python目录的目录。</span></p><p><span class="yiyi-st" id="yiyi-22">下面是一个示例Python 2.x源文件，<code class="file docutils literal"><span class="pre">example.py</span></code>：</span></p><pre><code class="language-python"><span></span><span class="k">def</span> <span class="nf">greet</span><span class="p">(</span><span class="n">name</span><span class="p">):</span>
    <span class="nb">print</span> <span class="s2">"Hello, </span><span class="si">{0}</span><span class="s2">!"</span><span class="o">.</span><span class="n">format</span><span class="p">(</span><span class="n">name</span><span class="p">)</span>
<span class="nb">print</span> <span class="s2">"What's your name?"</span>
<span class="n">name</span> <span class="o">=</span> <span class="n">raw_input</span><span class="p">()</span>
<span class="n">greet</span><span class="p">(</span><span class="n">name</span><span class="p">)</span>
</code></pre><p><span class="yiyi-st" id="yiyi-23">它可以通过命令行中的2to3转换为Python 3.x代码：</span></p><div class="highlight-shell-session"><div class="highlight"><pre><span></span><span class="gp">$</span> 2to3 example.py
</pre></div></div><p><span class="yiyi-st" id="yiyi-24">将打印与原始源文件的差异。</span><span class="yiyi-st" id="yiyi-25">2to3也可以将需要的修改写回源文件。</span><span class="yiyi-st" id="yiyi-26">（除非提供<code class="xref std std-option docutils literal"><span class="pre">-n</span></code>，否则将对原始文件进行备份。）</span><span class="yiyi-st" id="yiyi-27">使用<code class="xref std std-option docutils literal"><span class="pre">-w</span></code>标志启用写回更改：</span></p><div class="highlight-shell-session"><div class="highlight"><pre><span></span><span class="gp">$</span> 2to3 -w example.py
</pre></div></div><p><span class="yiyi-st" id="yiyi-28">转换后，<code class="file docutils literal"><span class="pre">example.py</span></code>如下所示：</span></p><pre><code class="language-python"><span></span><span class="k">def</span> <span class="nf">greet</span><span class="p">(</span><span class="n">name</span><span class="p">):</span>
    <span class="nb">print</span><span class="p">(</span><span class="s2">"Hello, </span><span class="si">{0}</span><span class="s2">!"</span><span class="o">.</span><span class="n">format</span><span class="p">(</span><span class="n">name</span><span class="p">))</span>
<span class="nb">print</span><span class="p">(</span><span class="s2">"What's your name?"</span><span class="p">)</span>
<span class="n">name</span> <span class="o">=</span> <span class="nb">input</span><span class="p">()</span>
<span class="n">greet</span><span class="p">(</span><span class="n">name</span><span class="p">)</span>
</code></pre><p><span class="yiyi-st" id="yiyi-29">在整个翻译过程中保留评论和精确缩进。</span></p><p><span class="yiyi-st" id="yiyi-30">默认情况下，2to3运行一组<a class="reference internal" href="#to3-fixers"><span>predefined fixers</span></a>。</span><span class="yiyi-st" id="yiyi-31"><code class="xref std std-option docutils literal"><span class="pre">-l</span></code></span><span class="yiyi-st" id="yiyi-32">可以使用<code class="xref std std-option docutils literal"><span class="pre">-f</span></code>给出要运行的一组明确的修复程序。同样，<code class="xref std std-option docutils literal"><span class="pre">-x</span></code>显式禁用修复程序。</span><span class="yiyi-st" id="yiyi-33">以下示例仅运行<code class="docutils literal"><span class="pre">imports</span></code>和<code class="docutils literal"><span class="pre">has_key</span></code>修复程序：</span></p><div class="highlight-shell-session"><div class="highlight"><pre><span></span><span class="gp">$</span> 2to3 -f imports -f has_key example.py
</pre></div></div><p><span class="yiyi-st" id="yiyi-34">此命令运行除了<code class="docutils literal"><span class="pre">apply</span></code>修订器之外的每个修订器：</span></p><div class="highlight-shell-session"><div class="highlight"><pre><span></span><span class="gp">$</span> 2to3 -x apply example.py
</pre></div></div><p><span class="yiyi-st" id="yiyi-35">一些修复程序是<em>显式</em>，意味着它们不是默认运行的，并且必须在命令行上列出以运行。</span><span class="yiyi-st" id="yiyi-36">这里，除了默认修复程序，<code class="docutils literal"><span class="pre">idioms</span></code>修复程序运行：</span></p><div class="highlight-shell-session"><div class="highlight"><pre><span></span><span class="gp">$</span> 2to3 -f all -f idioms example.py
</pre></div></div><p><span class="yiyi-st" id="yiyi-37">请注意如何通过<code class="docutils literal"><span class="pre">all</span></code>启用所有默认修正程序。</span></p><p><span class="yiyi-st" id="yiyi-38">有时2to3会在你的源代码中找到一个需要改变的地方，但2to3不能自动修复。</span><span class="yiyi-st" id="yiyi-39">在这种情况下，2to3将在文件的diff下面打印一个警告。</span><span class="yiyi-st" id="yiyi-40">您应该解决警告，以具有兼容的3.x代码。</span></p><p><span class="yiyi-st" id="yiyi-41">2to3也可以重构doctests。</span><span class="yiyi-st" id="yiyi-42">要启用此模式，请使用<code class="xref std std-option docutils literal"><span class="pre">-d</span></code>标志。</span><span class="yiyi-st" id="yiyi-43">请注意，<em>只有</em> doctests将被重构。</span><span class="yiyi-st" id="yiyi-44">这也不需要模块是有效的Python。</span><span class="yiyi-st" id="yiyi-45">例如，doctest like reST文档中的示例也可以使用此选项重构。</span></p><p><span class="yiyi-st" id="yiyi-46"><code class="xref std std-option docutils literal"><span class="pre">-v</span></code>选项允许输出有关翻译过程的更多信息。</span></p><p><span class="yiyi-st" id="yiyi-47">由于一些打印语句可以解析为函数调用或语句，因此2to3不能总是读取包含打印函数的文件。</span><span class="yiyi-st" id="yiyi-48">当2to3检测到<code class="docutils literal"><span class="pre">来自 t&gt; <span class="pre">__未来__</span> <span class="pre">导入</span> <span class="pre">print_function</span></span></code>编译器指令时，修改其内部语法以将<a class="reference internal" href="functions.html#print" title="print"><code class="xref py py-func docutils literal"><span class="pre">print()</span></code></a>解释为函数。</span><span class="yiyi-st" id="yiyi-49">此更改也可以使用<code class="xref std std-option docutils literal"><span class="pre">-p</span></code>标志手动启用。</span><span class="yiyi-st" id="yiyi-50">使用<code class="xref std std-option docutils literal"><span class="pre">-p</span></code>在已经转换其打印语句的代码上运行修复程序。</span></p><p><span class="yiyi-st" id="yiyi-51"><code class="xref std std-option docutils literal"><span class="pre">-o</span></code>或<code class="xref std std-option docutils literal"><span class="pre">--output-dir</span></code>选项允许指定要处理的输出文件的备用目录。</span><span class="yiyi-st" id="yiyi-52">当使用此作为备份文件时，如果不覆盖输入文件，则不需要使用<code class="xref std std-option docutils literal"><span class="pre">-n</span></code>标志。</span></p><div class="versionadded"><p><span class="yiyi-st" id="yiyi-53"><span class="versionmodified">版本3.2.3中的新功能：</span>添加了<code class="xref std std-option docutils literal"><span class="pre">-o</span></code>选项。</span></p></div><p><span class="yiyi-st" id="yiyi-54"><code class="xref std std-option docutils literal"><span class="pre">-W</span></code>或<code class="xref std std-option docutils literal"><span class="pre">--write-unchanged-files</span></code>标志告诉2to3始终写入输出文件，即使文件不需要更改。</span><span class="yiyi-st" id="yiyi-55">这对于<code class="xref std std-option docutils literal"><span class="pre">-o</span></code>最有用，因此整个Python源代码树将从一个目录转换为另一个目录。</span><span class="yiyi-st" id="yiyi-56">此选项意味着<code class="xref std std-option docutils literal"><span class="pre">-w</span></code>标志，因为它不会有意义。</span></p><div class="versionadded"><p><span class="yiyi-st" id="yiyi-57"><span class="versionmodified">版本3.2.3中的新功能：</span>添加了<code class="xref std std-option docutils literal"><span class="pre">-W</span></code>标志。</span></p></div><p><span class="yiyi-st" id="yiyi-58"><code class="xref std std-option docutils literal"><span class="pre">--add-suffix</span></code>选项指定要附加到所有输出文件名的字符串。</span><span class="yiyi-st" id="yiyi-59">指定此选项时需要<code class="xref std std-option docutils literal"><span class="pre">-n</span></code>标志，因为写入不同的文件名时不需要备份。</span><span class="yiyi-st" id="yiyi-60">例：</span></p><div class="highlight-shell-session"><div class="highlight"><pre><span></span><span class="gp">$</span> 2to3 -n -W --add-suffix<span class="o">=</span><span class="m">3</span> example.py
</pre></div></div><p><span class="yiyi-st" id="yiyi-61">将导致写入名为<code class="docutils literal"><span class="pre">example.py3</span></code>的转换文件。</span></p><div class="versionadded"><p><span class="yiyi-st" id="yiyi-62"><span class="versionmodified">版本3.2.3中的新功能：</span>添加了<code class="xref std std-option docutils literal"><span class="pre">--add-suffix</span></code>选项。</span></p></div><p><span class="yiyi-st" id="yiyi-63">要将整个项目从一个目录树翻译到另一个目录树，请使用：</span></p><div class="highlight-shell-session"><div class="highlight"><pre><span></span><span class="gp">$</span> 2to3 --output-dir<span class="o">=</span>python3-version/mycode -W -n python2-version/mycode
</pre></div></div></div><div class="section" id="fixers"><h2><span class="yiyi-st" id="yiyi-64">26.7.2. </span><span class="yiyi-st" id="yiyi-65">Fixers</span></h2><p><span class="yiyi-st" id="yiyi-66">转换代码的每个步骤都封装在修复程序中。</span><span class="yiyi-st" id="yiyi-67">命令<code class="docutils literal"><span class="pre">2to3</span> <span class="pre">-l </span></code>列出它们。</span><span class="yiyi-st" id="yiyi-68">由于<a class="reference internal" href="#to3-using"><span>documented above</span></a>，每个可以单独打开和关闭。</span><span class="yiyi-st" id="yiyi-69">这里更详细地描述它们。</span></p><dl class="2to3fixer"><dt id="2to3fixer-apply"><span class="yiyi-st" id="yiyi-70"> <code class="descname">apply</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-71">删除<code class="xref py py-func docutils literal"><span class="pre">apply()</span></code>的使用。</span><span class="yiyi-st" id="yiyi-72">例如<code class="docutils literal"><span class="pre">apply（function，</span> <span class="pre">* args，</span> <span class="pre">** kwargs）</span></code>转换为<code class="docutils literal"><span class="pre">函数（* args，</span> <span class="pre">** kwargs）</span></code>。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-asserts"><span class="yiyi-st" id="yiyi-73"> <code class="descname">asserts</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-74">用正确的方法替换已弃用的<a class="reference internal" href="unittest.html#module-unittest" title="unittest: Unit testing framework for Python."><code class="xref py py-mod docutils literal"><span class="pre">unittest</span></code></a>方法名称。</span></p><table border="1" class="docutils"><thead valign="bottom"><tr class="row-odd"><th class="head"><span class="yiyi-st" id="yiyi-75">从</span></th><th class="head"><span class="yiyi-st" id="yiyi-76">至</span></th></tr></thead><tbody valign="top"><tr class="row-even"><td><span class="yiyi-st" id="yiyi-77"><code class="docutils literal"><span class="pre">failUnlessEqual（a，</span> <span class="pre">b）</span></code></span></td><td><span class="yiyi-st" id="yiyi-78"><a class="reference internal" href="unittest.html#unittest.TestCase.assertEqual" title="unittest.TestCase.assertEqual"><code class="xref py py-meth docutils literal"><span class="pre">assertEqual(a,</span> <span class="pre">b)</span></code></a></span></td></tr><tr class="row-odd"><td><span class="yiyi-st" id="yiyi-79"><code class="docutils literal"><span class="pre">assertEquals（a，</span> <span class="pre">b）</span></code></span></td><td><span class="yiyi-st" id="yiyi-80"><a class="reference internal" href="unittest.html#unittest.TestCase.assertEqual" title="unittest.TestCase.assertEqual"><code class="xref py py-meth docutils literal"><span class="pre">assertEqual(a,</span> <span class="pre">b)</span></code></a></span></td></tr><tr class="row-even"><td><span class="yiyi-st" id="yiyi-81"><code class="docutils literal"><span class="pre">failIfEqual（a，</span> <span class="pre">b）</span></code></span></td><td><span class="yiyi-st" id="yiyi-82"><a class="reference internal" href="unittest.html#unittest.TestCase.assertNotEqual" title="unittest.TestCase.assertNotEqual"><code class="xref py py-meth docutils literal"><span class="pre">assertNotEqual(a,</span> <span class="pre">b)</span></code></a></span></td></tr><tr class="row-odd"><td><span class="yiyi-st" id="yiyi-83"><code class="docutils literal"><span class="pre">assertNotEquals（a，</span> <span class="pre">b）</span></code></span></td><td><span class="yiyi-st" id="yiyi-84"><a class="reference internal" href="unittest.html#unittest.TestCase.assertNotEqual" title="unittest.TestCase.assertNotEqual"><code class="xref py py-meth docutils literal"><span class="pre">assertNotEqual(a,</span> <span class="pre">b)</span></code></a></span></td></tr><tr class="row-even"><td><span class="yiyi-st" id="yiyi-85"><code class="docutils literal"><span class="pre">failUnless(a)</span></code></span></td><td><span class="yiyi-st" id="yiyi-86"><a class="reference internal" href="unittest.html#unittest.TestCase.assertTrue" title="unittest.TestCase.assertTrue"><code class="xref py py-meth docutils literal"><span class="pre">assertTrue(a)</span></code></a></span></td></tr><tr class="row-odd"><td><span class="yiyi-st" id="yiyi-87"><code class="docutils literal"><span class="pre">assert_(a)</span></code></span></td><td><span class="yiyi-st" id="yiyi-88"><a class="reference internal" href="unittest.html#unittest.TestCase.assertTrue" title="unittest.TestCase.assertTrue"><code class="xref py py-meth docutils literal"><span class="pre">assertTrue(a)</span></code></a></span></td></tr><tr class="row-even"><td><span class="yiyi-st" id="yiyi-89"><code class="docutils literal"><span class="pre">failIf(a)</span></code></span></td><td><span class="yiyi-st" id="yiyi-90"><a class="reference internal" href="unittest.html#unittest.TestCase.assertFalse" title="unittest.TestCase.assertFalse"><code class="xref py py-meth docutils literal"><span class="pre">assertFalse(a)</span></code></a></span></td></tr><tr class="row-odd"><td><span class="yiyi-st" id="yiyi-91"><code class="docutils literal"><span class="pre">failUnlessRaises（exc，</span> <span class="pre">cal）</span></code></span></td><td><span class="yiyi-st" id="yiyi-92"><a class="reference internal" href="unittest.html#unittest.TestCase.assertRaises" title="unittest.TestCase.assertRaises"><code class="xref py py-meth docutils literal"><span class="pre">assertRaises(exc,</span> <span class="pre">cal)</span></code></a></span></td></tr><tr class="row-even"><td><span class="yiyi-st" id="yiyi-93"><code class="docutils literal"><span class="pre">failUnlessAlmostEqual（a，</span> <span class="pre">b）</span></code></span></td><td><span class="yiyi-st" id="yiyi-94"><a class="reference internal" href="unittest.html#unittest.TestCase.assertAlmostEqual" title="unittest.TestCase.assertAlmostEqual"><code class="xref py py-meth docutils literal"><span class="pre">assertAlmostEqual(a,</span> <span class="pre">b)</span></code></a></span></td></tr><tr class="row-odd"><td><span class="yiyi-st" id="yiyi-95"><code class="docutils literal"><span class="pre">assertAlmostEquals（a，</span> <span class="pre">b）</span></code></span></td><td><span class="yiyi-st" id="yiyi-96"><a class="reference internal" href="unittest.html#unittest.TestCase.assertAlmostEqual" title="unittest.TestCase.assertAlmostEqual"><code class="xref py py-meth docutils literal"><span class="pre">assertAlmostEqual(a,</span> <span class="pre">b)</span></code></a></span></td></tr><tr class="row-even"><td><span class="yiyi-st" id="yiyi-97"><code class="docutils literal"><span class="pre">failIfAlmostEqual（a，</span> <span class="pre">b）</span></code></span></td><td><span class="yiyi-st" id="yiyi-98"><a class="reference internal" href="unittest.html#unittest.TestCase.assertNotAlmostEqual" title="unittest.TestCase.assertNotAlmostEqual"><code class="xref py py-meth docutils literal"><span class="pre">assertNotAlmostEqual(a,</span> <span class="pre">b)</span></code></a></span></td></tr><tr class="row-odd"><td><span class="yiyi-st" id="yiyi-99"><code class="docutils literal"><span class="pre">assertNotAlmostEquals（a，</span> <span class="pre">b）</span></code></span></td><td><span class="yiyi-st" id="yiyi-100"><a class="reference internal" href="unittest.html#unittest.TestCase.assertNotAlmostEqual" title="unittest.TestCase.assertNotAlmostEqual"><code class="xref py py-meth docutils literal"><span class="pre">assertNotAlmostEqual(a,</span> <span class="pre">b)</span></code></a></span></td></tr></tbody></table></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-basestring"><span class="yiyi-st" id="yiyi-101"> <code class="descname">basestring</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-102">将<code class="xref py py-class docutils literal"><span class="pre">basestring</span></code>转换为<a class="reference internal" href="stdtypes.html#str" title="str"><code class="xref py py-class docutils literal"><span class="pre">str</span></code></a>。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-buffer"><span class="yiyi-st" id="yiyi-103"> <code class="descname">buffer</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-104">将<code class="xref py py-class docutils literal"><span class="pre">buffer</span></code>转换为<a class="reference internal" href="stdtypes.html#memoryview" title="memoryview"><code class="xref py py-class docutils literal"><span class="pre">memoryview</span></code></a>。</span><span class="yiyi-st" id="yiyi-105">此修订器是可选的，因为<a class="reference internal" href="stdtypes.html#memoryview" title="memoryview"><code class="xref py py-class docutils literal"><span class="pre">memoryview</span></code></a> API与<code class="xref py py-class docutils literal"><span class="pre">buffer</span></code>类似，但不完全相同。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-callable"><span class="yiyi-st" id="yiyi-106"> <code class="descname">callable</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-107">将<code class="docutils literal"><span class="pre">callable(x)</span></code>转换为<code class="docutils literal"><span class="pre">isinstance（x，</span> <span class="pre">collections.Callable）</span></code>，向<a class="reference internal" href="collections.html#module-collections" title="collections: Container datatypes"><code class="xref py py-mod docutils literal"><span class="pre">collections</span></code></a>，如果需要的话。</span><span class="yiyi-st" id="yiyi-108">注意<code class="docutils literal"><span class="pre">callable(x)</span></code>在Python 3.2中返回，所以如果你不打算支持Python 3.1，你可以禁用这个修复软件。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-dict"><span class="yiyi-st" id="yiyi-109"> <code class="descname">dict</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-110">修复字典迭代方法。</span><span class="yiyi-st" id="yiyi-111"><code class="xref py py-meth docutils literal"><span class="pre">dict.iteritems()</span></code> is converted to <a class="reference internal" href="stdtypes.html#dict.items" title="dict.items"><code class="xref py py-meth docutils literal"><span class="pre">dict.items()</span></code></a>, <code class="xref py py-meth docutils literal"><span class="pre">dict.iterkeys()</span></code> to <a class="reference internal" href="stdtypes.html#dict.keys" title="dict.keys"><code class="xref py py-meth docutils literal"><span class="pre">dict.keys()</span></code></a>, and <code class="xref py py-meth docutils literal"><span class="pre">dict.itervalues()</span></code> to <a class="reference internal" href="stdtypes.html#dict.values" title="dict.values"><code class="xref py py-meth docutils literal"><span class="pre">dict.values()</span></code></a>. </span><span class="yiyi-st" id="yiyi-112">同样，<code class="xref py py-meth docutils literal"><span class="pre">dict.viewitems()</span></code>，<code class="xref py py-meth docutils literal"><span class="pre">dict.viewkeys()</span></code>和<code class="xref py py-meth docutils literal"><span class="pre">dict.viewvalues()</span></code>分别转换为<a class="reference internal" href="stdtypes.html#dict.items" title="dict.items"><code class="xref py py-meth docutils literal"><span class="pre">dict.items()</span></code></a>，<a class="reference internal" href="stdtypes.html#dict.keys" title="dict.keys"><code class="xref py py-meth docutils literal"><span class="pre">dict.keys()</span></code></a>和<a class="reference internal" href="stdtypes.html#dict.values" title="dict.values"><code class="xref py py-meth docutils literal"><span class="pre">dict.values()</span></code></a>。</span><span class="yiyi-st" id="yiyi-113">It also wraps existing usages of <a class="reference internal" href="stdtypes.html#dict.items" title="dict.items"><code class="xref py py-meth docutils literal"><span class="pre">dict.items()</span></code></a>, <a class="reference internal" href="stdtypes.html#dict.keys" title="dict.keys"><code class="xref py py-meth docutils literal"><span class="pre">dict.keys()</span></code></a>, and <a class="reference internal" href="stdtypes.html#dict.values" title="dict.values"><code class="xref py py-meth docutils literal"><span class="pre">dict.values()</span></code></a> in a call to <a class="reference internal" href="stdtypes.html#list" title="list"><code class="xref py py-class docutils literal"><span class="pre">list</span></code></a>.</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-except"><span class="yiyi-st" id="yiyi-114"> <code class="descname">except</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-115">Converts <code class="docutils literal"><span class="pre">except</span> <span class="pre">X,</span> <span class="pre">T</span></code> to <code class="docutils literal"><span class="pre">except</span> <span class="pre">X</span> <span class="pre">as</span> <span class="pre">T</span></code>.</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-exec"><span class="yiyi-st" id="yiyi-116"> <code class="descname">exec</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-117">将<code class="docutils literal"><span class="pre">exec</span></code>语句转换为<a class="reference internal" href="functions.html#exec" title="exec"><code class="xref py py-func docutils literal"><span class="pre">exec()</span></code></a>函数。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-execfile"><span class="yiyi-st" id="yiyi-118"> <code class="descname">execfile</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-119">删除<code class="xref py py-func docutils literal"><span class="pre">execfile()</span></code>的使用。</span><span class="yiyi-st" id="yiyi-120"><code class="xref py py-func docutils literal"><span class="pre">execfile()</span></code>的参数包含在<a class="reference internal" href="functions.html#open" title="open"><code class="xref py py-func docutils literal"><span class="pre">open()</span></code></a>，<a class="reference internal" href="functions.html#compile" title="compile"><code class="xref py py-func docutils literal"><span class="pre">compile()</span></code></a>和<a class="reference internal" href="functions.html#exec" title="exec"><code class="xref py py-func docutils literal"><span class="pre">exec()</span></code></a></span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-exitfunc"><span class="yiyi-st" id="yiyi-121"> <code class="descname">exitfunc</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-122">更改<code class="xref py py-attr docutils literal"><span class="pre">sys.exitfunc</span></code>的分配以使用<a class="reference internal" href="atexit.html#module-atexit" title="atexit: Register and execute cleanup functions."><code class="xref py py-mod docutils literal"><span class="pre">atexit</span></code></a>模块。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-filter"><span class="yiyi-st" id="yiyi-123"> <code class="descname">filter</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-124">在<a class="reference internal" href="stdtypes.html#list" title="list"><code class="xref py py-class docutils literal"><span class="pre">list</span></code></a>调用中使用<a class="reference internal" href="functions.html#filter" title="filter"><code class="xref py py-func docutils literal"><span class="pre">filter()</span></code></a>使用。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-funcattrs"><span class="yiyi-st" id="yiyi-125"> <code class="descname">funcattrs</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-126">修复已重命名的函数属性。</span><span class="yiyi-st" id="yiyi-127">例如，<code class="docutils literal"><span class="pre">my_function.func_closure</span></code>将转换为<code class="docutils literal"><span class="pre">my_function.__closure__</span></code>。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-future"><span class="yiyi-st" id="yiyi-128"> <code class="descname">future</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-129">从 <span class="pre">__未来__</span> <span class="pre">导入</span> <span class="pre">new_feature</span>语句中删除<code class="docutils literal"><span class="pre"></span></code></span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-getcwdu"><span class="yiyi-st" id="yiyi-130"> <code class="descname">getcwdu</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-131">将<code class="xref py py-func docutils literal"><span class="pre">os.getcwdu()</span></code>重命名为<a class="reference internal" href="os.html#os.getcwd" title="os.getcwd"><code class="xref py py-func docutils literal"><span class="pre">os.getcwd()</span></code></a>。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-has_key"><span class="yiyi-st" id="yiyi-132"> <code class="descname">has_key</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-133">在 <span class="pre">dict</span>中将<code class="docutils literal"><span class="pre">dict.has_key(key)</span></code>更改为<code class="docutils literal"><span class="pre">键</span> <span class="pre">。</span></code></span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-idioms"><span class="yiyi-st" id="yiyi-134"> <code class="descname">idioms</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-135">这个可选的修复程序执行几个转换，使Python代码更惯用。</span><span class="yiyi-st" id="yiyi-136">Type comparisons like <code class="docutils literal"><span class="pre">type(x)</span> <span class="pre">is</span> <span class="pre">SomeClass</span></code> and <code class="docutils literal"><span class="pre">type(x)</span> <span class="pre">==</span> <span class="pre">SomeClass</span></code> are converted to <code class="docutils literal"><span class="pre">isinstance(x,</span> <span class="pre">SomeClass)</span></code>. </span><span class="yiyi-st" id="yiyi-137"><code class="docutils literal"><span class="pre">，而</span> <span class="pre">1</span></code>成为<code class="docutils literal"><span class="pre">，而</span> <span class="pre"></span></code></span><span class="yiyi-st" id="yiyi-138">此修复程序还尝试在适当的地方使用<a class="reference internal" href="functions.html#sorted" title="sorted"><code class="xref py py-func docutils literal"><span class="pre">sorted()</span></code></a>。</span><span class="yiyi-st" id="yiyi-139">例如，这个块</span></p><pre><code class="language-python"><span></span><span class="n">L</span> <span class="o">=</span> <span class="nb">list</span><span class="p">(</span><span class="n">some_iterable</span><span class="p">)</span>
<span class="n">L</span><span class="o">.</span><span class="n">sort</span><span class="p">()</span>
</code></pre><p><span class="yiyi-st" id="yiyi-140">改为</span></p><pre><code class="language-python"><span></span><span class="n">L</span> <span class="o">=</span> <span class="nb">sorted</span><span class="p">(</span><span class="n">some_iterable</span><span class="p">)</span>
</code></pre></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-import"><span class="yiyi-st" id="yiyi-141"> <code class="descname">import</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-142">检测兄弟导入，并将其转换为相对导入。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-imports"><span class="yiyi-st" id="yiyi-143"> <code class="descname">imports</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-144">处理标准库中的模块重命名。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-imports2"><span class="yiyi-st" id="yiyi-145"> <code class="descname">imports2</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-146">处理标准库中的其他模块重命名。</span><span class="yiyi-st" id="yiyi-147">它仅与<a class="reference internal" href="#2to3fixer-imports"><code class="xref std std-2to3fixer docutils literal"><span class="pre">imports</span></code></a>固定程序分开，因为存在技术限制。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-input"><span class="yiyi-st" id="yiyi-148"> <code class="descname">input</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-149">将<code class="docutils literal"><span class="pre">input(prompt)</span></code>转换为<code class="docutils literal"><span class="pre">eval(input(prompt))</span></code>。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-intern"><span class="yiyi-st" id="yiyi-150"> <code class="descname">intern</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-151">将<code class="xref py py-func docutils literal"><span class="pre">intern()</span></code>转换为<a class="reference internal" href="sys.html#sys.intern" title="sys.intern"><code class="xref py py-func docutils literal"><span class="pre">sys.intern()</span></code></a>。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-isinstance"><span class="yiyi-st" id="yiyi-152"> <code class="descname">isinstance</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-153">修复<a class="reference internal" href="functions.html#isinstance" title="isinstance"><code class="xref py py-func docutils literal"><span class="pre">isinstance()</span></code></a>的第二个参数中的重复类型。</span><span class="yiyi-st" id="yiyi-154">例如，<code class="docutils literal"><span class="pre">isinstance（x，</span> <span class="pre">（int，</span> <span class="pre">int））</span></code>被转换为<code class="docutils literal"><span class="pre">isinstance（x，</span> <span class="pre">（int））</span></code>。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-itertools_imports"><span class="yiyi-st" id="yiyi-155"> <code class="descname">itertools_imports</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-156">删除<code class="xref py py-func docutils literal"><span class="pre">itertools.ifilter()</span></code>，<code class="xref py py-func docutils literal"><span class="pre">itertools.izip()</span></code>和<code class="xref py py-func docutils literal"><span class="pre">itertools.imap()</span></code>的导入。</span><span class="yiyi-st" id="yiyi-157">导入<code class="xref py py-func docutils literal"><span class="pre">itertools.ifilterfalse()</span></code>也会更改为<a class="reference internal" href="itertools.html#itertools.filterfalse" title="itertools.filterfalse"><code class="xref py py-func docutils literal"><span class="pre">itertools.filterfalse()</span></code></a>。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-itertools"><span class="yiyi-st" id="yiyi-158"> <code class="descname">itertools</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-159">将<code class="xref py py-func docutils literal"><span class="pre">itertools.ifilter()</span></code>，<code class="xref py py-func docutils literal"><span class="pre">itertools.izip()</span></code>和<code class="xref py py-func docutils literal"><span class="pre">itertools.imap()</span></code>的用法更改为其内建等效项。</span><span class="yiyi-st" id="yiyi-160"><code class="xref py py-func docutils literal"><span class="pre">itertools.ifilterfalse()</span></code>更改为<a class="reference internal" href="itertools.html#itertools.filterfalse" title="itertools.filterfalse"><code class="xref py py-func docutils literal"><span class="pre">itertools.filterfalse()</span></code></a>。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-long"><span class="yiyi-st" id="yiyi-161"> <code class="descname">long</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-162">将<code class="xref py py-class docutils literal"><span class="pre">long</span></code>重命名为<a class="reference internal" href="functions.html#int" title="int"><code class="xref py py-class docutils literal"><span class="pre">int</span></code></a>。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-map"><span class="yiyi-st" id="yiyi-163"> <code class="descname">map</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-164">在<a class="reference internal" href="stdtypes.html#list" title="list"><code class="xref py py-class docutils literal"><span class="pre">list</span></code></a>调用中换行<a class="reference internal" href="functions.html#map" title="map"><code class="xref py py-func docutils literal"><span class="pre">map()</span></code></a>。</span><span class="yiyi-st" id="yiyi-165">它还会更改<code class="docutils literal"><span class="pre">映射（无，</span> <span class="pre">x）</span></code>到<code class="docutils literal"><span class="pre">list(x)</span></code></span><span class="yiyi-st" id="yiyi-166">使用<code class="docutils literal"><span class="pre">从</span> <span class="pre">future_builtins</span> <span class="pre">导入</span> <span class="pre">地图</span></code>禁用此修复程序。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-metaclass"><span class="yiyi-st" id="yiyi-167"> <code class="descname">metaclass</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-168">Converts the old metaclass syntax (<code class="docutils literal"><span class="pre">__metaclass__</span> <span class="pre">=</span> <span class="pre">Meta</span></code> in the class body) to the new (<code class="docutils literal"><span class="pre">class</span> <span class="pre">X(metaclass=Meta)</span></code>).</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-methodattrs"><span class="yiyi-st" id="yiyi-169"> <code class="descname">methodattrs</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-170">修复旧方法属性名称。</span><span class="yiyi-st" id="yiyi-171">例如，<code class="docutils literal"><span class="pre">meth.im_func</span></code>被转换为<code class="docutils literal"><span class="pre">meth.__func__</span></code>。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-ne"><span class="yiyi-st" id="yiyi-172"> <code class="descname">ne</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-173">将旧的不等式语法<code class="docutils literal"><span class="pre">&lt;&gt;</span></code>转换为<code class="docutils literal"><span class="pre">!=</span></code>。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-next"><span class="yiyi-st" id="yiyi-174"> <code class="descname">next</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-175">将迭代器的<code class="xref py py-meth docutils literal"><span class="pre">next()</span></code>方法转换为<a class="reference internal" href="functions.html#next" title="next"><code class="xref py py-func docutils literal"><span class="pre">next()</span></code></a>函数。</span><span class="yiyi-st" id="yiyi-176">它还将<a class="reference internal" href="functions.html#next" title="next"><code class="xref py py-meth docutils literal"><span class="pre">next()</span></code></a>方法重命名为<a class="reference internal" href="stdtypes.html#iterator.__next__" title="iterator.__next__"><code class="xref py py-meth docutils literal"><span class="pre">__next__()</span></code></a>。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-nonzero"><span class="yiyi-st" id="yiyi-177"> <code class="descname">nonzero</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-178">将<code class="xref py py-meth docutils literal"><span class="pre">__nonzero__()</span></code>重命名为<a class="reference internal" href="../reference/datamodel.html#object.__bool__" title="object.__bool__"><code class="xref py py-meth docutils literal"><span class="pre">__bool__()</span></code></a>。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-numliterals"><span class="yiyi-st" id="yiyi-179"> <code class="descname">numliterals</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-180">将八进制字面值转换为新的语法。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-operator"><span class="yiyi-st" id="yiyi-181"> <code class="descname">operator</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-182">将对<a class="reference internal" href="operator.html#module-operator" title="operator: Functions corresponding to the standard operators."><code class="xref py py-mod docutils literal"><span class="pre">operator</span></code></a>模块中各种函数的调用转换为其他函数，但等价的函数调用。</span><span class="yiyi-st" id="yiyi-183">需要时，添加适当的<code class="docutils literal"><span class="pre">import</span></code>语句，例如</span><span class="yiyi-st" id="yiyi-184"><code class="docutils literal"><span class="pre">import</span> <span class="pre">容器</span></code>。</span><span class="yiyi-st" id="yiyi-185">进行以下映射：</span></p><table border="1" class="docutils"><thead valign="bottom"><tr class="row-odd"><th class="head"><span class="yiyi-st" id="yiyi-186">从</span></th><th class="head"><span class="yiyi-st" id="yiyi-187">至</span></th></tr></thead><tbody valign="top"><tr class="row-even"><td><span class="yiyi-st" id="yiyi-188"><code class="docutils literal"><span class="pre">operator.isCallable(obj)</span></code></span></td><td><span class="yiyi-st" id="yiyi-189"><code class="docutils literal"><span class="pre">hasattr（obj，</span> <span class="pre">'__ call __'）</span></code></span></td></tr><tr class="row-odd"><td><span class="yiyi-st" id="yiyi-190"><code class="docutils literal"><span class="pre">operator.sequenceIncludes(obj)</span></code></span></td><td><span class="yiyi-st" id="yiyi-191"><code class="docutils literal"><span class="pre">operator.contains(obj)</span></code></span></td></tr><tr class="row-even"><td><span class="yiyi-st" id="yiyi-192"><code class="docutils literal"><span class="pre">operator.isSequenceType(obj)</span></code></span></td><td><span class="yiyi-st" id="yiyi-193"><code class="docutils literal"><span class="pre">isinstance（obj，</span> <span class="pre">容器。序列）</span></code></span></td></tr><tr class="row-odd"><td><span class="yiyi-st" id="yiyi-194"><code class="docutils literal"><span class="pre">operator.isMappingType(obj)</span></code></span></td><td><span class="yiyi-st" id="yiyi-195"><code class="docutils literal"><span class="pre">isinstance（obj，</span> <span class="pre">容器.Mapping）</span></code></span></td></tr><tr class="row-even"><td><span class="yiyi-st" id="yiyi-196"><code class="docutils literal"><span class="pre">operator.isNumberType(obj)</span></code></span></td><td><span class="yiyi-st" id="yiyi-197"><code class="docutils literal"><span class="pre">isinstance（obj，</span> <span class="pre">numbers.Number）</span></code></span></td></tr><tr class="row-odd"><td><span class="yiyi-st" id="yiyi-198"><code class="docutils literal"><span class="pre">operator.repeat（obj，</span> <span class="pre">n）</span></code></span></td><td><span class="yiyi-st" id="yiyi-199"><code class="docutils literal"><span class="pre">operator.mul（obj，</span> <span class="pre">n）</span></code></span></td></tr><tr class="row-even"><td><span class="yiyi-st" id="yiyi-200"><code class="docutils literal"><span class="pre">operator.irepeat（obj，</span> <span class="pre">n）</span></code></span></td><td><span class="yiyi-st" id="yiyi-201"><code class="docutils literal"><span class="pre">operator.imul（obj，</span> <span class="pre">n）</span></code></span></td></tr></tbody></table></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-paren"><span class="yiyi-st" id="yiyi-202"> <code class="descname">paren</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-203">在列表推导式中添加需要的括号。</span><span class="yiyi-st" id="yiyi-204">For example, <code class="docutils literal"><span class="pre">[x</span> <span class="pre">for</span> <span class="pre">x</span> <span class="pre">in</span> <span class="pre">1,</span> <span class="pre">2]</span></code> becomes <code class="docutils literal"><span class="pre">[x</span> <span class="pre">for</span> <span class="pre">x</span> <span class="pre">in</span> <span class="pre">(1,</span> <span class="pre">2)]</span></code>.</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-print"><span class="yiyi-st" id="yiyi-205"> <code class="descname">print</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-206">将<code class="docutils literal"><span class="pre">print</span></code>语句转换为<a class="reference internal" href="functions.html#print" title="print"><code class="xref py py-func docutils literal"><span class="pre">print()</span></code></a>函数。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-raise"><span class="yiyi-st" id="yiyi-207"> <code class="descname">raise</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-208">转换<code class="docutils literal"><span class="pre">提高</span> <span class="pre">E，</span> <span class="pre">V</span></code>至<code class="docutils literal"><span class="pre">提高</span> <span class="pre">E V）</span></code>和<code class="docutils literal"><span class="pre">提高</span> <span class="pre">E，</span> <span class="pre">V，</span> <span class="pre">/ t7&gt;到<code class="docutils literal"><span class="pre">提高</span> <span class="pre">E（V）.with_traceback（T）</span></code>。</span></code></span><span class="yiyi-st" id="yiyi-209">如果<code class="docutils literal"><span class="pre">E</span></code>是元组，则翻译将不正确，因为替换元组在3.0中已除去异常。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-raw_input"><span class="yiyi-st" id="yiyi-210"> <code class="descname">raw_input</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-211">将<code class="xref py py-func docutils literal"><span class="pre">raw_input()</span></code>转换为<a class="reference internal" href="functions.html#input" title="input"><code class="xref py py-func docutils literal"><span class="pre">input()</span></code></a>。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-reduce"><span class="yiyi-st" id="yiyi-212"> <code class="descname">reduce</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-213">处理<code class="xref py py-func docutils literal"><span class="pre">reduce()</span></code>到<a class="reference internal" href="functools.html#functools.reduce" title="functools.reduce"><code class="xref py py-func docutils literal"><span class="pre">functools.reduce()</span></code></a>的移动。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-reload"><span class="yiyi-st" id="yiyi-214"> <code class="descname">reload</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-215">将<code class="xref py py-func docutils literal"><span class="pre">reload()</span></code>转换为<a class="reference internal" href="imp.html#imp.reload" title="imp.reload"><code class="xref py py-func docutils literal"><span class="pre">imp.reload()</span></code></a>。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-renames"><span class="yiyi-st" id="yiyi-216"> <code class="descname">renames</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-217">将<code class="xref py py-data docutils literal"><span class="pre">sys.maxint</span></code>更改为<a class="reference internal" href="sys.html#sys.maxsize" title="sys.maxsize"><code class="xref py py-data docutils literal"><span class="pre">sys.maxsize</span></code></a>。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-repr"><span class="yiyi-st" id="yiyi-218"> <code class="descname">repr</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-219">用<a class="reference internal" href="functions.html#repr" title="repr"><code class="xref py py-func docutils literal"><span class="pre">repr()</span></code></a>函数替换backtick repr。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-set_literal"><span class="yiyi-st" id="yiyi-220"> <code class="descname">set_literal</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-221">用set字面值替换<a class="reference internal" href="stdtypes.html#set" title="set"><code class="xref py py-class docutils literal"><span class="pre">set</span></code></a>构造函数的使用。</span><span class="yiyi-st" id="yiyi-222">此修订包是可选的。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-standarderror"><span class="yiyi-st" id="yiyi-223"> <code class="descname">standarderror</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-224">将<code class="xref py py-exc docutils literal"><span class="pre">StandardError</span></code>重命名为<a class="reference internal" href="exceptions.html#Exception" title="Exception"><code class="xref py py-exc docutils literal"><span class="pre">Exception</span></code></a>。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-sys_exc"><span class="yiyi-st" id="yiyi-225"> <code class="descname">sys_exc</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-226">更改已弃用的<code class="xref py py-data docutils literal"><span class="pre">sys.exc_value</span></code>，<code class="xref py py-data docutils literal"><span class="pre">sys.exc_type</span></code>，<code class="xref py py-data docutils literal"><span class="pre">sys.exc_traceback</span></code>以使用<a class="reference internal" href="sys.html#sys.exc_info" title="sys.exc_info"><code class="xref py py-func docutils literal"><span class="pre">sys.exc_info()</span></code></a>。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-throw"><span class="yiyi-st" id="yiyi-227"> <code class="descname">throw</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-228">修复生成器的<code class="xref py py-meth docutils literal"><span class="pre">throw()</span></code>方法中的API更改。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-tuple_params"><span class="yiyi-st" id="yiyi-229"> <code class="descname">tuple_params</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-230">删除隐式元组参数分拆。</span><span class="yiyi-st" id="yiyi-231">此修订包插入临时变量。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-types"><span class="yiyi-st" id="yiyi-232"> <code class="descname">types</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-233">修复因删除<a class="reference internal" href="types.html#module-types" title="types: Names for built-in types."><code class="xref py py-mod docutils literal"><span class="pre">types</span></code></a>模块中的某些成员而导致的代码。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-unicode"><span class="yiyi-st" id="yiyi-234"> <code class="descname">unicode</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-235">将<code class="xref py py-class docutils literal"><span class="pre">unicode</span></code>重命名为<a class="reference internal" href="stdtypes.html#str" title="str"><code class="xref py py-class docutils literal"><span class="pre">str</span></code></a>。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-urllib"><span class="yiyi-st" id="yiyi-236"> <code class="descname">urllib</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-237">处理<a class="reference internal" href="urllib.html#module-urllib" title="urllib"><code class="xref py py-mod docutils literal"><span class="pre">urllib</span></code></a>和<code class="xref py py-mod docutils literal"><span class="pre">urllib2</span></code>的重命名为<a class="reference internal" href="urllib.html#module-urllib" title="urllib"><code class="xref py py-mod docutils literal"><span class="pre">urllib</span></code></a>包。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-ws_comma"><span class="yiyi-st" id="yiyi-238"> <code class="descname">ws_comma</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-239">从逗号分隔的项目中删除多余的空格。</span><span class="yiyi-st" id="yiyi-240">此修订包是可选的。</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-xrange"><span class="yiyi-st" id="yiyi-241"> <code class="descname">xrange</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-242">将<code class="xref py py-func docutils literal"><span class="pre">xrange()</span></code>重新命名为<a class="reference internal" href="stdtypes.html#range" title="range"><code class="xref py py-func docutils literal"><span class="pre">range()</span></code></a>并用<a class="reference internal" href="stdtypes.html#list" title="list"><code class="xref py py-class docutils literal"><span class="pre">list</span></code></a>包装现有<a class="reference internal" href="stdtypes.html#range" title="range"><code class="xref py py-func docutils literal"><span class="pre">range()</span></code></a></span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-xreadlines"><span class="yiyi-st" id="yiyi-243"> <code class="descname">xreadlines</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-244">Changes <code class="docutils literal"><span class="pre">for</span> <span class="pre">x</span> <span class="pre">in</span> <span class="pre">file.xreadlines()</span></code> to <code class="docutils literal"><span class="pre">for</span> <span class="pre">x</span> <span class="pre">in</span> <span class="pre">file</span></code>.</span></p></dd></dl><dl class="2to3fixer"><dt id="2to3fixer-zip"><span class="yiyi-st" id="yiyi-245"> <code class="descname">zip</code></span></dt><dd><p><span class="yiyi-st" id="yiyi-246">在<a class="reference internal" href="stdtypes.html#list" title="list"><code class="xref py py-class docutils literal"><span class="pre">list</span></code></a>调用中封装<a class="reference internal" href="functions.html#zip" title="zip"><code class="xref py py-func docutils literal"><span class="pre">zip()</span></code></a>使用。</span><span class="yiyi-st" id="yiyi-247">当出现<code class="docutils literal"><span class="pre">从</span> <span class="pre">future_builtins</span> <span class="pre">import</span> <span class="pre">zip</span></code>时，</span></p></dd></dl></div><div class="section" id="module-lib2to3"><h2><span class="yiyi-st" id="yiyi-248">26.7.3. <a class="reference internal" href="#module-lib2to3" title="lib2to3: the 2to3 library"><code class="xref py py-mod docutils literal"><span class="pre">lib2to3</span></code></a>  -  2to3的库</span></h2><p><span class="yiyi-st" id="yiyi-249"><strong>源代码：</strong> <a class="reference external" href="https://hg.python.org/cpython/file/3.5/Lib/lib2to3/">Lib/lib2to3/</a></span></p><div class="admonition note"><p class="first admonition-title"><span class="yiyi-st" id="yiyi-250">注意</span></p><p class="last"><span class="yiyi-st" id="yiyi-251"><a class="reference internal" href="#module-lib2to3" title="lib2to3: the 2to3 library"><code class="xref py py-mod docutils literal"><span class="pre">lib2to3</span></code></a> API应被视为不稳定，并且将来可能会发生巨大变化。</span></p></div></div></div></div>