You can use this package
https://pypi.org/project/heic-to-jpg/
Just convert one picture?
Run this command on terminal
heic-to-jpg -s ~/path/to/source [--keep]
But you need to install imagemagick
brew install imagemagick
Convert pictures in a directory?
import glob
import os
fs = glob.glob('*.heic')
for f in fs:
print(f)
os.system('heic-to-jpg -s ' + f)