title: How to install git+https:// from setup.py using install_requires
body: <p>I have a project in which I have to install from git+https:</p>
  
  <p>I can make it to work in this way:</p>
  
  <pre><code>virtualenv -p python3.5 bla
  . bla/bin/activate
  pip install numpy # must have numpy before the following pkg...
  pip install 'git+https://github.com/cocodataset/cocoapi.git#subdirectory=PythonAPI'
  </code></pre>
  
  <p>However, I want to use it in a setup.py file in <code>install_requires</code>:</p>
  
  <pre><code>from setuptools import setup
  setup(install_requires='git+https://github.com/cocodataset/cocoapi.git#subdirectory=PythonAPI', setup_requires='numpy')
  </code></pre>
  
  <p>and then, <code>pip install -e .</code> from the dir containing the <code>setup.py</code></p>
  
  <p>This doesn't work due to parse error: </p>
  
  <pre><code>    Complete output (1 lines):                                                                                                             
      error in bla_bla setup command: 'install_requires' must be a string or list of strings containing valid project/version requireme
  nt specifiers; Invalid requirement, parse error at "'+https:/'"                                                                             
      ----------------------------------------
  ERROR: Command errored out with exit status 1: python setup.py egg_info Check the logs for full command output.  
  </code></pre>
  
  <p>The error doesn't occur if I install using <code>pip install -r requires.txt</code> (assuming I have the same string in that file) and not when using direct <code>pip install git+...</code>...</p>
  
  <p>How to fix this parsing error?</p>
  
  <p>What I've tried so far:</p>
  
  <ol>
  <li>wrapping the string with " / """ / ' / '''</li>
  <li>adding 'r' before the string</li>
  </ol>