ModuleNotFoundError: No module named 'PIL'

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python3.6 -m pip install --upgrade pip

python3.6 -m pip install --upgrade Pillow 

#! /usr/bin/python3.6

# Use python3.6 [name of python script]
# Much help from ironfoot and karel
 
import os
import sys
from PIL import Image
 
if len(sys.argv) > 1:
    if os.path.exists(sys.argv[1]):
        im = Image.open(sys.argv[1])
        target_name = sys.argv[1] + ".jpg"
        rgb_im = im.convert('RGB')
        rgb_im.save(target_name)
        print("Saved as " + target_name)
    else:
        print(sys.argv[1] + " not found")
else:
    print("Usage: convert2jpg.py <file>")