title: ModuleNotFoundError: No module named 'serial'
body: <p>This is Arduino Python.</p>
  
  <p>The Python script is giving me an error with the following line:</p>
  
  <p><code>import serial</code></p>
  
  <p>The error is:</p>
  
  <p><code>ModuleNotFoundError: No module named 'serial'</code></p>
  
  <p>I want to understand the relationship between the software libraries.  where is the serial library? 
  I think the library is there, but the present Python script is not finding it.<br>
  john</p>