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Sempre que eu executar o comandopip install Django Recebo o seguinte rastreamento de erro, o que significa que há algum conflito de versão. Tentei desinstalar e instalar o mesmo pacote, mas está apresentando o mesmo err

Downloading/unpacking bcrypt (from Django)
  Downloading bcrypt-2.0.0.tar.gz
  Running setup.py (path:/tmp/pip_build_root/bcrypt/setup.py) egg_info for package bcrypt
    Traceback (most recent call last):
      File "<string>", line 17, in <module>
      File "/tmp/pip_build_root/bcrypt/setup.py", line 226, in <module>
        **keywords_with_side_effects(sys.argv)
      File "/usr/lib/python2.7/distutils/core.py", line 111, in setup
        _setup_distribution = dist = klass(attrs)
      File "/usr/local/lib/python2.7/dist-packages/distribute-0.6.28-py2.7.egg/setuptools/dist.py", line 225, in __init__
        _Distribution.__init__(self,attrs)
      File "/usr/lib/python2.7/distutils/dist.py", line 287, in __init__
        self.finalize_options()
      File "/usr/local/lib/python2.7/dist-packages/distribute-0.6.28-py2.7.egg/setuptools/dist.py", line 257, in finalize_options
        ep.require(installer=self.fetch_build_egg)
      File "/usr/local/lib/python2.7/dist-packages/distribute-0.6.28-py2.7.egg/pkg_resources.py", line 2029, in require
        working_set.resolve(self.dist.requires(self.extras),env,installer))
      File "/usr/local/lib/python2.7/dist-packages/distribute-0.6.28-py2.7.egg/pkg_resources.py", line 592, in resolve
        raise VersionConflict(dist,req) # XXX put more info here
    pkg_resources.VersionConflict: (certifi 2016.2.28 (/usr/local/lib/python2.7/dist-packages), Requirement.parse('certifi==2015.11.20'))
    Complete output from command python setup.py egg_info:
    Traceback (most recent call last):

  File "<string>", line 17, in <module>

  File "/tmp/pip_build_root/bcrypt/setup.py", line 226, in <module>

    **keywords_with_side_effects(sys.argv)

  File "/usr/lib/python2.7/distutils/core.py", line 111, in setup

    _setup_distribution = dist = klass(attrs)

  File "/usr/local/lib/python2.7/dist-packages/distribute-0.6.28-py2.7.egg/setuptools/dist.py", line 225, in __init__

    _Distribution.__init__(self,attrs)

  File "/usr/lib/python2.7/distutils/dist.py", line 287, in __init__

    self.finalize_options()

  File "/usr/local/lib/python2.7/dist-packages/distribute-0.6.28-py2.7.egg/setuptools/dist.py", line 257, in finalize_options

    ep.require(installer=self.fetch_build_egg)

  File "/usr/local/lib/python2.7/dist-packages/distribute-0.6.28-py2.7.egg/pkg_resources.py", line 2029, in require

    working_set.resolve(self.dist.requires(self.extras),env,installer))

  File "/usr/local/lib/python2.7/dist-packages/distribute-0.6.28-py2.7.egg/pkg_resources.py", line 592, in resolve

    raise VersionConflict(dist,req) # XXX put more info here

pkg_resources.VersionConflict: (certifi 2016.2.28 (/usr/local/lib/python2.7/dist-packages), Requirement.parse('certifi==2015.11.20'))

----------------------------------------
Cleaning up...

Estou usando Python 2.7. Alguém sabe qual é o problema?