How to fetch environment variables in Mac OS X using python?

How can I lookup envi开发者_高级运维ronment variables (e.g. export HG_USER from .profile) using python code in Mac OS X?

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os.environ is a dictionary containing all the environment variables. You need to import os before you can use it. So, for example HG_USER would be accessed by os.environ['HG_USER'].

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Use the os module:

import os
os.environ

Returns a dictionary with the environment variables as keys.

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Use os:

>>> import os
>>> print os.environ["PATH"]

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You can also the helper function os.getenv(varname[, value]) which will return the value of environment variable varname, and if it not present will return value which defaults to None