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    <h1><a href="http://wbowam.github.io/python-exeche-evalyu-ju.html"> python exec和eval语句  </a></h1>
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            <h5 id="execpythonpythonexec">exec语句用来执行储存在字符串或文件中的Python语句。例如，我们可以在运行时生成一个包含Python代码的字符串，然后使用exec语句执行这些语句。下面是一个简单的例子。<a class="headerlink" href="#execpythonpythonexec" title="Permanent link">&para;</a></h5>
<div class="highlight"><pre><span class="o">&gt;&gt;&gt;</span> <span class="n">exec</span> <span class="err">&#39;</span><span class="n">print</span> <span class="s">&quot;Hello World&quot;</span><span class="err">&#39;</span>
<span class="n">Hello</span> <span class="n">World</span>
</pre></div>


<h6 id="evalpython">eval语句用来计算存储在字符串中的有效Python表达式。下面是一个简单的例子。<a class="headerlink" href="#evalpython" title="Permanent link">&para;</a></h6>
<div class="highlight"><pre><span class="o">&gt;&gt;&gt;</span> <span class="n">eval</span><span class="p">(</span><span class="err">&#39;</span><span class="mi">2</span><span class="o">*</span><span class="mi">3</span><span class="err">&#39;</span><span class="p">)</span>
<span class="mi">6</span>
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            <h4>Published</h4>
            <time pubdate="pubdate" datetime="2014-07-02T00:00:00+08:00">Jul 2, 2014</time>
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