Access environment variables from Python -

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i set environment variable want access in python application. how value?

environment variables accessed through os.environ

import os print os.environ['home']

or can see list of environment variables using:

os.environ

as might need see complete list!

# using return `none` if key not present rather raise `keyerror` print os.environ.get('key_that_might_exist')  # os.getenv equivalent, , can give default value instead of `none` print os.getenv('key_that_might_exist', default_value)

python default installation on windows c:\python. if want find out while running python can do:

import sys print sys.prefix

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