sys.stdin to do a word count based on user entry

[Kaltex]

Hi all

I have been using the sys module's stdinput to take input from the user until they enter the keyword 'submit'. Once this happens the dictionary would have stored the key:value pairs for what has been inputted up to this point.
The key:value pairs should print to the user.

The issue I am having is that I can't stop the std input with the keyword 'submit', curious why this is?

import sys
dictionary_words = {}
for line in sys.stdin:
    for word in line.split():
        if word == 'submit':
            break
        else:
            dictionary_words[word] = dictionary_words.get(word,0) + 1
for key,value in dictionary_words.items():
    print(key,value)

If its of any help, when I compile this py file, I run it in a linux terminal.

Much appreciated

P.S Unfortunately do have to use stdin :)