import sys

if __name__ == '__main__':
	print(sum(map(float, sys.argv[1:])))

import sys

def add_all(nums):
	return sum(nums)

if __name__ == '__main__':
	command = sys.argv[1]
	nums = map(float, sys.argv[2:])
	if command == 'add':
		print(add_all(nums))

Add support for commands