title: pip install pickle not working - no such file or directory
body: <p>Ubuntu 16.04 LTS, trying to install cpickle with pip. I've searched a bit, haven't found anything useful yet. </p>
  
  <p>PYTHONPATH isn't set.</p>
  
  <h1>Error message</h1>
  
  <pre><code>user@hostname:~$ sudo -H pip3 install cpickle
  Collecting cpickle
    Using cached cpickle-0.5.tar.gz
      Complete output from command python setup.py egg_info:
      Traceback (most recent call last):
        File "&lt;string&gt;", line 1, in &lt;module&gt;
        File "/usr/lib/python3.5/tokenize.py", line 454, in open
          buffer = _builtin_open(filename, 'rb')
      FileNotFoundError: [Errno 2] No such file or directory: '/tmp/pip-build-wn926hef/cpickle/setup.py'
  
      ----------------------------------------
  Command "python setup.py egg_info" failed with error code 1 in /tmp/pip-build-wn926hef/cpickle/
  You are using pip version 8.1.1, however version 9.0.1 is available.
  You should consider upgrading via the 'pip install --upgrade pip' command.
  
  
      ----------------------------------------
  Command "python setup.py egg_info" failed with error code 1 in /tmp/pip-build-q46tq1l8/cpickle/
  You are using pip version 8.1.1, however version 9.0.1 is available.
  You should consider upgrading via the 'pip install --upgrade pip' command.
  </code></pre>
  
  <h1>troubleshooting steps</h1>
  
  <pre><code># version info
  user@hostname:~$ python --version
  Python 2.7.12
  user@hostname:~$ python3 --version
  Python 3.5.2
  
  # I don't think cache is the problem
  rm -rf ~/.cache/
  sudo -H pip install  cpickle --no-cache-dir # same problem
  sudo -H pip3 install  cpickle --no-cache-dir # same problem
  </code></pre>