title: ModuleNotFoundError: No module named 'PIL' after upgrading Python 3.5 to Python 3.7 for Raspberry Pi 3
body: <p>Like what the title said, after ugrading my Python to 3.7, the camera app won't work anymore and give me errors:</p>
  <pre><code>Traceback (most recent call last):
    File &quot;PiCameraApp.py&quot;, line 38, in &lt;module&gt;
      from    AnnotationOverlay   import *
    File &quot;/home/pi/PiCameraApp-master/Source/AnnotationOverlay.py&quot;, line 52, in &lt;module&gt;
      from    Dialog  import *
    File &quot;/home/pi/PiCameraApp-master/Source/Dialog.py&quot;, line 42, in &lt;module&gt;
      import PIL
  ModuleNotFoundError: No module named 'PIL'
  </code></pre>
  <p>I've tried re-installing pillow using 'pip3 install pillow'and Successfully installed <code>pillow-7.2.0</code>  but still won't able to import PIL.
  Appreciate anyone's input. Thanks</p>