DJANGO cannot import name _compare_digest

[Xristos Xristoou]

hello i have python 7.13

DJANGO 1.11.2 version

django-crypto 0.20 version on windows 10.

i want to create a DJANGO app but anytime to try to migrate i take

that error :

    from django.utils.crypto import get_random_string
  File "C:\Python27\lib\site-packages\django\utils\crypto.py", line 8, in <module>
    import hmac
  File "C:\Python27\Lib\hmac.py", line 8, in <module>
    from operator import _compare_digest as compare_digest
ImportError: cannot import name _compare_digest

how to fix it ?