擅长:python、mysql、java
<p>假设您知道键中的值是有效的,为什么不一起放弃异常并检查键呢?你知道吗</p>
<pre><code>for item in old_dicts:
if 'dog1' in item:
new_dict['key1'] = item['dog1'][0:5]
if 'dog2' in item:
new_dict['key2'] = item['dog2'][0:10]
if 'dog3' in item:
new_dict['key3'] = item['dog3'][0:3]
if 'dog4' in item:
new_dict['key4'] = item['dog4'][3:11]
</code></pre>