title: Setuptools "development" Requirements
body: <p><strong>TL;DR</strong>: Is there a way to hook setuptool's 'develop' to install a set of development requirements when running <code>python setup.py develop</code>? </p>
  
  <p>I'm building my first python package using setuptools. I'm specifying the requirements as:</p>
  
  <pre><code>requirements = [
      'click',
      'ansible',
      'fabric',
      'gitpython',
      'pyyaml',
      'jinja2',
      'yapsy'
  ]
  
  test_requirements = [
      'pytest',
      'pytest-pep8',
      'pytest-cov',
  ]
  
  setup(
  ...
      install_requires=requirements,
      tests_require=test_requirements,
  ...
  )
  </code></pre>
  
  <p>During development, I've been installing the package (in a virtual environment) with:</p>
  
  <pre><code>python setup.py develop
  </code></pre>
  
  <p>and uninstalling with:</p>
  
  <pre><code>python setup.py develop -u
  </code></pre>
  
  <p>The package uses entry_points to install some command line scripts, so this sets up the commands for me and allows me to edit the package while testing the command at the same time.</p>
  
  <p>I also have some dependencies that I use for development ... sphinx + extensions and a couple other things (things that aren't needed to use the package). I'm just manually installing them in the virtual environment at the moment. I didn't see any documentation (and haven't found any examples on the googles) about how to wire them in with setuptools.</p>
  
  <p>Maybe there's a way to hook 'setup.py develop' to install an additional set of requirements? Another method I haven't read about?</p>