title: Python setup.py: Could not find suitable distribution for Requirement.parse('tensorflow')
body: <p>I have <code>tensorflow</code> listed as a requirement in the <code>install_requires</code> section of the <code>setup.py</code> of my project.</p>
  
  <p>When I attempt to install my project into a new Anaconda environment I get the following error:</p>
  
  <pre><code>$ python setup.py install
  
  ...
  
  Searching for tensorflow
  Reading https://pypi.org/simple/tensorflow/
  No local packages or working download links found for tensorflow
  error: Could not find suitable distribution for Requirement.parse('tensorflow')
  </code></pre>
  
  <p>I can get past this by installing tensorflow "manually" via conda:</p>
  
  <pre><code>$ conda install tensorflow
  </code></pre>
  
  <p>Once I do this the install via <code>setup.py</code> works without a hitch.</p>
  
  <p>Am I mistaken in assuming that something is amiss with my environment? If not then what is going on and how can I avoid this issue? (My concern is that users of my package will not be able to install from source using <code>setup.py</code>)</p>
  
  <p>Another oddity that I assume is related or may provide a clue is that the version of TensorFlow listed in my Anaconda environment is 2.0 but if I import it when running Python it appears to instead be using version 1.15. For example:</p>
  
  <pre><code>$ conda list tensorflow
  # packages in environment at /home/james/miniconda3/envs/cvdata_test:
  #
  # Name                    Version                   Build  Channel
  tensorflow                2.0.0           mkl_py37h66b46cc_0  
  tensorflow-base           2.0.0           mkl_py37h9204916_0  
  tensorflow-estimator      2.0.0              pyh2649769_0  
  
  $ python 
  Python 3.7.6 | packaged by conda-forge | (default, Jan  7 2020, 22:33:48) 
  [GCC 7.3.0] on linux
  Type "help", "copyright", "credits" or "license" for more information.
  &gt;&gt;&gt; import tensorflow as tf
  &gt;&gt;&gt; tf.__version__
  '1.15.0-rc2'
  </code></pre>
  
  <p>This is on a Dell laptop running Ubuntu 18.04 without a GPU, so perhaps the version shown in the interpreter is akin to <code>tensorflow-cpu</code>? If I run <code>pip freeze</code> I see <code>tensorflow==2.0.0</code> and <code>tensorflow-cpu==1.15.0rc2</code>, which is a bit confusing...</p>