How to decide the balance of the pie percentage?

Trying to get this running on my Mac. Installed VS Code. Installed pip, installed numpy etc. Now when I run it within VS Code with Python 3 I get:

chantal@Gonzo effecient_frontier % /usr/bin/python3 /Users/chantal/Documents/GitHub/effecient_frontier/effecient_frontier.py
Traceback (most recent call last):
  File "/Users/chantal/Documents/GitHub/effecient_frontier/effecient_frontier.py", line 1, in <module>
    import numpy as np
ModuleNotFoundError: No module named 'numpy'

Any help appreciated!