title: No module named cv2 error in Python Raspberry
body: <p>I am having this error when I try to run a Python file. I tried opening a new terminal and importing cv2 worked there in Python but doesn't work in my OpenCV virtual environment. I don't even understand how virtualenvs work but I have to find a solution for this.</p>
  
  <pre><code>&gt; (cv) pi@raspberrypi:~/Camerafeed $ python run.py Traceback (most
  &gt; recent call last):   File "run.py", line 2, in &lt;module&gt;
  &gt;     from camerafeed import CameraFeed   File "/home/pi/Camerafeed/camerafeed/__init__.py", line 5, in &lt;module&gt;
  &gt;     import cv2 ImportError: No module named 'cv2'
  </code></pre>