title: modulenotfounderror no module named 'networkx' python3
body: <p>I am using python3 and I installed networkx and I import it in my code. When I run my python code file in command line (<code>python3 file.py</code>), I get the following error:</p>
  <pre><code>ModuleNotFoundError: No module named 'networkx'
  </code></pre>
  <p>While when I run <code>python3</code> in command line and I import networkx, it will be imported well, without any error:
  <a href="https://i.stack.imgur.com/LBXmP.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/LBXmP.jpg" alt="enter image description here" /></a></p>
  <p>What the problem is?</p>