title: conda installed some package but still ModuleNotFoundError when import this package
body: <p>I've found the solution:<a href="https://stackoverflow.com/questions/33433274/anaconda-graphviz-cant-import-after-installation">anaconda - graphviz - can&#39;t import after installation</a></p>
  
  <p>I want to use <code>graphviz</code> and follow the commend in <a href="https://anaconda.org/anaconda/graphviz" rel="nofollow noreferrer">https://anaconda.org/anaconda/graphviz</a></p>
  
  <p>run following in terminal</p>
  
  <p><code>conda install -c anaconda graphviz</code></p>
  
  <p>However no matter in Jupyter Notebook, python or Pycharm to <code>import graphviz</code>, it always shows </p>
  
  <p><code>ModuleNotFoundError: No module named 'graphviz'</code></p>
  
  <p>How to solve this problem? Thank you.</p>
  
  <p>PS:</p>
  
  <ol>
  <li><p>when run <code>which python</code> in terminal: it return <code>/opt/anaconda3/bin/python</code>, therefore I use anaconda environment by default. And I have only one environment in anaconda that is <code>root</code>. </p></li>
  <li><p>when I run <code>conda list</code> in terminal, I can find this line : </p></li>
  </ol>
  
  <p><code>graphviz                  2.40.1               hefbbd9a_2</code></p>
  
  <ol start="3">
  <li>I found a weird thing: </li>
  </ol>
  
  <p>my <code>pip</code> and <code>conda</code> use the same environment:</p>
  
  <p>run :<code>which pip</code> </p>
  
  <p>get : <code>/opt/anaconda3/bin/pip</code></p>
  
  <p>run : <code>which conda</code></p>
  
  <p>get : <code>/opt/anaconda3/bin/conda</code></p>
  
  <p>However when I run <code>pip list</code>, I cannot find <code>graphviz</code> and many other packages which shows in <code>conda list</code>. For these packages show in <code>conda list</code> but not in <code>pip list</code>, I also cannot import them no matter in Jupyter notebook, python, pycharm etc. Why this happens?</p>