Please fix this error in Python. Here was the assignment.

from sys import argv def longest_ word(fn_input): file_inputopen (mary.txt, "r") maxLength0 maxWord = "" for line in file_input: for word in line.split(" "): if maxlength len (word): maxLengthlen (word) maxWord -word return maxword if _name_ "main__"; fn-in-argv [1]1 print(longest_word(fn_in)) In [17]: runfile ("/Users/Jay/Desktop/LAB/ untitled1.py', wdir- /Users/Jay/Desktop/ LAB') Traceback (most recent call last): File "", line 1, in runfile("/Users/Jay/Desktop/LAB/ untitled 1 . py. LAB') wdir-'/Users/Jay/Desktop/ File "/anaconda3/lib/python3.7/site packages/spyder_kernels/customize/ spydercustomize.py", line 704, in runfile execfile(filename, namespace) File "/anaconda3/lib/python3.7/site packages/spyder_kernels/customize/ spydercustomize.py", line 108, in execfile exec(compile(f.read(), filename, 'exec) namespace) File "/Users/Jay/Desktop/LAB/ untitled1.py", line 22, in fn inargv [1] IndexError: list index out of range 1. (10 Points) Write a program that prints the word that has the longest length, in terms of the number of characters, in the supplied text file. Show your output to the TA on the following text files: mary.txt and frost.txt