如何解决AttributeError:'_Environ'对象没有属性'has_key' [英] how to solve AttributeError: '_Environ' object has no attribute 'has_key'
本文介绍了如何解决AttributeError:'_Environ'对象没有属性'has_key'的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!
问题描述
def _is_dev_mode():
# quick hack to check if the program is running in dev mode.
# if 'has_key' in os.environ
if os.environ.has_key('SERVER_SOFTWARE') \
or os.environ.has_key('PHP_FCGI_CHILDREN') \
or 'fcgi' in sys.argv or 'fastcgi' in sys.argv \
or 'mod_wsgi' in sys.argv:
return False
return True
在上面的代码中出现错误显示
in above code following error is shown
if os.environ.has_key('SERVER_SOFTWARE') \
AttributeError: '_Environ' object has no attribute 'has_key'
推荐答案
我想你正在python 3.在Python 2中,字典有一个 has_key()
方法。在Python 3中,正如异常所述,它不再存在。您需要使用运算符中的:
I supose you are working on python 3. In Python 2, dictionaries had a has_key()
method. In Python 3, as the exception says, it no longer exists. You need to use the in
operator:
if 'SERVER_SOFTWARE' in os.environ
这里有一个例子(py3k):
here you have an example (py3k):
>>> import os
>>> if 'PROCESSOR_LEVEL' in os.environ: print(os.environ['PROCESSOR_LEVEL'])
6
>>> if os.environ.has_key('PROCESSOR_LEVEL'): print("fail")
Traceback (most recent call last):
File "<pyshell#18>", line 1, in <module>
if os.environ.has_key('PROCESSOR_LEVEL'): print("fail")
AttributeError: '_Environ' object has no attribute 'has_key'
>>>
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