Traceback (most recent call last):
  File "/usr/bin/pip3", line 11, in <module>
    load_entry_point('pip==20.0.2', 'console_scripts', 'pip3')()
  File "/usr/lib/python3.6/site-packages/pkg_resources/__init__.py", line 484, in load_entry_point
    return get_distribution(dist).load_entry_point(group, name)
  File "/usr/lib/python3.6/site-packages/pkg_resources/__init__.py", line 2725, in load_entry_point
    return ep.load()
  File "/usr/lib/python3.6/site-packages/pkg_resources/__init__.py", line 2343, in load
    return self.resolve()
  File "/usr/lib/python3.6/site-packages/pkg_resources/__init__.py", line 2349, in resolve
    module = __import__(self.module_name, fromlist=['__name__'], level=0)
  File "/usr/lib/python3.6/site-packages/pip/_internal/cli/main.py", line 10, in <module>
    from pip._internal.cli.autocompletion import autocomplete
  File "/usr/lib/python3.6/site-packages/pip/_internal/cli/autocompletion.py", line 9, in <module>
    from pip._internal.cli.main_parser import create_main_parser
  File "/usr/lib/python3.6/site-packages/pip/_internal/cli/main_parser.py", line 7, in <module>
    from pip._internal.cli import cmdoptions
  File "/usr/lib/python3.6/site-packages/pip/_internal/cli/cmdoptions.py", line 25, in <module>
    from pip._internal.locations import USER_CACHE_DIR, get_src_prefix
  File "/usr/lib/python3.6/site-packages/pip/_internal/locations/__init__.py", line 7, in <module>
    from pip._internal.models.scheme import SCHEME_KEYS, Scheme
ImportError: cannot import name 'SCHEME_KEYS'