title: Installing package halo gives error: 'install_requires' must be a string or list of strings containing valid project/version requirement specifiers
body: <p>Im trying to install Halo by using,</p>
  
  <pre><code>pip install halo
  </code></pre>
  
  <p>I get the following error message: </p>
  
  <pre><code>    ERROR: Command errored out with exit status 1:
       command: /usr/bin/python -c 'import sys, setuptools, tokenize; sys.argv[0] = '"'"'/private/var/folders/9s/vjh90rsn4xl5587hr11qpjjh0000gn/T/pip-install-L5LD_D/halo/setup.py'"'"'; __file__='"'"'/private/var/folders/9s/vjh90rsn4xl5587hr11qpjjh0000gn/T/pip-install-L5LD_D/halo/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' egg_info --egg-base /private/var/folders/9s/vjh90rsn4xl5587hr11qpjjh0000gn/T/pip-install-L5LD_D/halo/pip-egg-info
           cwd: /private/var/folders/9s/vjh90rsn4xl5587hr11qpjjh0000gn/T/pip-install-L5LD_D/halo/
      Complete output (3 lines):
      /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/distutils/dist.py:267: UserWarning: Unknown distribution option: 'long_description_content_type'
        warnings.warn(msg)
      error in halo setup command: 'install_requires' must be a string or list of strings containing valid project/version requirement specifiers; Expected ',' or end-of-list in backports.shutil_get_terminal_size&gt;=1.0.0;python_version &lt; '3.3' at ;python_version &lt; '3.3'
      ----------------------------------------
  ERROR: Command errored out with exit status 1: python setup.py egg_info Check the logs for full command output.
  </code></pre>
  
  <p>My python version is 2.7.10. </p>
  
  <p>I made some research and tried the following solutions, </p>
  
  <pre><code>brew install halo 
  </code></pre>
  
  <p>This did not work and my terminal returned: </p>
  
  <pre><code>Error: No formulae found in taps.
  </code></pre>
  
  <p>I checked my Formulae in Homebrew and could not find Halo. However, I found other packages so my Homebrew work otherwise. </p>
  
  <p>I tried chaning my python version to 3 by changing alias and installing halo again, and it did not work either. </p>
  
  <pre><code>alias python='python3'
  </code></pre>
  
  <p>Error massage was the same as for python2, as above. </p>
  
  <p>I need halo for a school lab, and im using Mac.</p>
  
  <p></p>