title: Python : ModuleNotFoundError: No module named 'youtube_dl'
body: <p>I have to use <strong>youtube-dl</strong> for a program.
  When I try to execute my program with the command <code>python downloader.py</code>, my porgram start correctly, but when I try to execute directly my script with the command <code>downloader.py</code>, I get the following error :
  <code>ModuleNotFoundError: No module named 'youtube_dl'</code></p>
  <p>I already tried the following commands to install correctly youtube_dl :</p>
  <pre><code>pip install youtube-dl
  pip3 install youtube-dl
  pip install --upgrade youtube-dl
  </code></pre>
  <p>but it doesn't resolve my problem.</p>
  <p>I think it's because I can't import a module with <strong>-</strong> with python3 so I have to import it with <strong>_</strong> and windows don't recognize it.
  Thank's by advance for helping me</p>