ment phase.  For instance, I need Sphinx in the development phase
to build the documentation.</p>
<p>setup.py is used to created a distribution (in Windows terms, an installer).  It may not need all the components
needed in the development phase. For instance, my installed application does not build documentaiton, therefore
it does not need Sphinx.</p>
<div class="admonition tip">
<p class="first admonition-title">Tip</p>
<p class="last">Packages in setup.py are normally in requirements.txt.
Most packages i