# "PEP 8(E731): do not assign a lambda expression, use a def"

在解决[python多层嵌套字典KeyError](https://github.com/huataihuang/cloud-atlas-draft/tree/6f3204fffc11cf006abd394631e2598d98b415c3/develop/python/startup/nested_dictionary_key_error/README.md)时候，我使用了 `lambda`的方法来构建一个复杂的嵌套字典，能够正常运行，但是在使用Python开发IDC（使用sublime+SimplePythonIDC）发现在以下这段代码第一行

```
mydict = lambda: defaultdict(mydict)
vm_perf = mydict()
```

有如下提示信息：

```
[W] PEP 8(E731): do not assign a lambda expression, use a def, 3 matches
```

## 参考


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