https://www.youtube.com/watch?v=dsG36BlV_HI&list=PLaE61CK5r6_l2fxVp3r3OP0fgTSTdQUoQ&index=9&t=0s
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import sys
num=int(sys.argv[1])
for each in range(1,10):
print(num,"x",each,"=",num*each)
python this_file.py 4