So confused about this following code, can you explain this following code, like what they do (the copy of code also provide under the picture below)

import sys

filename = sys.argv[1] try: number = int(sys.argv[2]) except ValueError: exit("Extension number must be a valid integer.")

lines = [] with open(filename, "r") as f: lines = f.readlines()

try: f = open(filename + number, "w") except ValueError: exit()

i = 0 while i files.py 1 import sys 2 3 filename sys.argv[1] 4 try: 5 ... number = int(sys.argv[2]) 6 except ValueError: 7 exit("Extension number must be a valid integer.") 8 9 lines = [] 10 with open(filename, "r") as f: 11 lines = f.readlines () 12 13 try: 14 ... f = open(filename + number, "w") 15 except ValueError: 16 exit() 17 18 i = 0 19 while i