# Error:
error: argument ... expected one argument
# Explanation:
# In my case, I was passing an argument that was meant as a comma-separated
# list of numbers and the first number was negative, e.g.: -10,20. It seems
# that the Argparse module had trouble interpreting the argument and was
# treating the -10 as a new parameter such that the previous parameter was
# getting no values, hence the "expected one argument" error.
# Solution
# To solve this I had to surround the argument with quotes and place a space
# in front of the virst number, e.g.: " -10,20"