title: Installation of TensorFlow on windows 7 - 'pip3' is not recognized as an internal or external command,
body: <p>When following the Installing TensorFlow for Windows guide <a href="https://www.tensorflow.org/install/install_windows" rel="noreferrer">https://www.tensorflow.org/install/install_windows</a>, after executing</p>
  
  <pre><code>C:\&gt; pip3 install --upgrade tensorflow
  </code></pre>
  
  <p>I get the following error:</p>
  
  <pre><code>'pip3' is not recognized as an internal or external command,
  </code></pre>
  
  <p>It looks like pip3 isn't recognized at all (although PATH to python is set)</p>