字典的方法

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          <h3 id="python">《Python 教程》授课笔记附件</h3>
<ul>
<li>讲师: 魏明择</li>
<li>时间: 2019</li>
</ul>
<h4 id="_1">字典的方法 </h4>
<table>
<thead>
<tr>
<th>方法</th>
<th>说明</th>
</tr>
</thead>
<tbody>
<tr>
<td>D代表字典对象</td>
<td></td>
</tr>
<tr>
<td>D.clear()</td>
<td>清空字典</td>
</tr>
<tr>
<td>D.pop(key)</td>
<td>移除键，同时返回此键所对应的值</td>
</tr>
<tr>
<td>D.copy()</td>
<td>返回字典D的副本,只复制一层(浅拷贝)</td>
</tr>
<tr>
<td>D.update(D2)</td>
<td>将字典 D2 合并到D中，如果键相同，则此键的值取D2的值作为新值</td>
</tr>
<tr>
<td>D.get(key, default=None)</td>
<td>返回键key所对应的值,如果没有此键，则返回default</td>
</tr>
<tr>
<td></td>
<td></td>
</tr>
<tr>
<td>D.keys()</td>
<td>返回可迭代的 dict_keys 集合对象</td>
</tr>
<tr>
<td>D.values()</td>
<td>返回可迭代的 dict_values 值对象</td>
</tr>
<tr>
<td>D.items()</td>
<td>返回可迭代的 dict_items 对象</td>
</tr>
</tbody>
</table>
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