I'm trying to install selenium library for python on my Ubuntu machine using pip installer.
I receive the following error:

pip install selenium
Exception: Traceback (most recent call last):   File
  "/usr/lib/python2.7/dist-packages/pip/basecommand.py", line 122, in
  main
      status = self.run(options, args)   File "/usr/lib/python2.7/dist-packages/pip/commands/install.py", line 304,
  in run
      requirement_set.prepare_files(finder, force_root_egg_info=self.bundle, bundle=self.bundle)   File
  "/usr/lib/python2.7/dist-packages/pip/req.py", line 1230, in
  prepare_files
      req_to_install.run_egg_info()   File "/usr/lib/python2.7/dist-packages/pip/req.py", line 293, in
  run_egg_info
      logger.notify('Running setup.py (path:%s) egg_info for package %s' % (self.setup_py, self.name))   File
  "/usr/lib/python2.7/dist-packages/pip/req.py", line 285, in setup_py
      if six.PY2 and isinstance(setup_py, six.text_type): AttributeError: 'module' object has no attribute 'PY2'

I am currently using Python 2.7.9

python --version
Python 2.7.9
Solved upgrading six

pip install --upgrade six
Can't install python selenium on Ubuntu 14.10/15.04(pre-release)