pip uninstall fails for egg package

Question

My app is distributed as an .egg file. Users successfully install egg with easy_install

$ sudo easy_install abcdef-1.0.0-py2.7.egg

Unfortunately uninstallation fails:

$ sudo pip uninstall abcdef

Uninstalling abcdef-1.0.0:
  /usr/local/lib/python2.7/dist-packages/abcdef-1.0.0-py2.7.egg
Proceed (y/n)? y
  Successfully uninstalled abcdef-1.0.0
Traceback (most recent call last):
  File "/usr/local/bin/pip", line 11, in <module>
    sys.exit(main())
  File "/usr/local/lib/python2.7/dist-packages/pip/__init__.py", line 233, in main
    return command.main(cmd_args)
  File "/usr/local/lib/python2.7/dist-packages/pip/basecommand.py", line 252, in main
    pip_version_check(session)
  File "/usr/local/lib/python2.7/dist-packages/pip/utils/outdated.py", line 102, in pip_version_check
    installed_version = get_installed_version("pip")
  File "/usr/local/lib/python2.7/dist-packages/pip/utils/__init__.py", line 838, in get_installed_version
    working_set = pkg_resources.WorkingSet()
  File "/usr/local/lib/python2.7/dist-packages/pip/_vendor/pkg_resources/__init__.py", line 644, in __init__
    self.add_entry(entry)
  File "/usr/local/lib/python2.7/dist-packages/pip/_vendor/pkg_resources/__init__.py", line 700, in add_entry
    for dist in find_distributions(entry, True):
  File "/usr/local/lib/python2.7/dist-packages/pip/_vendor/pkg_resources/__init__.py", line 1949, in find_eggs_in_zip
    if metadata.has_metadata('PKG-INFO'):
  File "/usr/local/lib/python2.7/dist-packages/pip/_vendor/pkg_resources/__init__.py", line 1463, in has_metadata
    return self.egg_info and self._has(self._fn(self.egg_info, name))
  File "/usr/local/lib/python2.7/dist-packages/pip/_vendor/pkg_resources/__init__.py", line 1823, in _has
    return zip_path in self.zipinfo or zip_path in self._index()
  File "/usr/local/lib/python2.7/dist-packages/pip/_vendor/pkg_resources/__init__.py", line 1703, in zipinfo
    return self._zip_manifests.load(self.loader.archive)
  File "/usr/local/lib/python2.7/dist-packages/pip/_vendor/pkg_resources/__init__.py", line 1643, in load
    mtime = os.stat(path).st_mtime
OSError: [Errno 2] No such file or directory: '/usr/local/lib/python2.7/dist-packages/abcdef-1.0.0-py2.7.egg'

And console script is still present in /usr/local/bin/

$ abcdef
Traceback (most recent call last):
  File "/usr/local/bin/abcdef", line 6, in <module>
    from pkg_resources import load_entry_point
  File "/usr/local/lib/python2.7/dist-packages/pkg_resources/__init__.py", line 3019, in <module>
    @_call_aside
  File "/usr/local/lib/python2.7/dist-packages/pkg_resources/__init__.py", line 3003, in _call_aside
    f(*args, **kwargs)
  File "/usr/local/lib/python2.7/dist-packages/pkg_resources/__init__.py", line 3032, in _initialize_master_working_set
    working_set = WorkingSet._build_master()
  File "/usr/local/lib/python2.7/dist-packages/pkg_resources/__init__.py", line 655, in _build_master
    ws.require(__requires__)
  File "/usr/local/lib/python2.7/dist-packages/pkg_resources/__init__.py", line 963, in require
    needed = self.resolve(parse_requirements(requirements))
  File "/usr/local/lib/python2.7/dist-packages/pkg_resources/__init__.py", line 849, in resolve
    raise DistributionNotFound(req, requirers)
pkg_resources.DistributionNotFound: The 'abcdef==1.0.0' distribution was not found and is required by the application

Here my setup.py

from setuptools import setup

setup(
    name='abcdef',
    version='1.0.0',
    packages=['abcdef'],
    entry_points={
        'console_scripts': [
            'abcdef = abcdef.abcdef:main',
        ],
    },
)

How to fix it? Anything is missing in setup.py?

$pip --version
pip 9.0.1 from /usr/local/lib/python2.7/dist-packages (python 2.7)

$ python --version
Python 2.7.11+