word_counter.py

# A small utility to read any txt file and output the number of words

import sys
import re
from collections import Counter

def word_count(fname):
        # This is the ignore word list
        ignore_words = [ "the" , "of", "to", "and", "in", "is" , "a", "this", "that", "for", "with", "was", "on", "have", "it", "he", "are", "not", "but" ]
        
        total_words = 0
        
        # We are going to open the file, convert words to lower, and filter all the words
        # Then we count the words using Counter
        with open(fname) as f:
                data = re.findall(r"[\w']+",(f.read().lower()))
                words = Counter(data)
        
        # We then print out the data in a tabulated format, except for those words in the ignore list
        # But we will stil count the ignored words for the final tally.
        # lambda is used to sort. We are sorting by the count and then by the word
        for word, key in sorted(words.items() , key=lambda x: (x[1] , x[0])):
            if word in ignore_words:
                total_words = total_words+ key
                continue
            else :
                total_words = total_words+ key
                print ('{0:15} {1:5}'.format(word, key)) # This formats the output nicely
                
        return total_words

def main():
       
        #Only try something if a filename is passed as argument
        try:
            filename = sys.argv[1]
            print (filename)
            print("Number of words in the file :",word_count(filename))
        except IndexError as e:
            print ("you need to specify the filename")
            


if __name__ == "__main__":
        main()

usage:
$python3 word_counter.py

👍 BTW, use most_common method of Counter instead of the sorted line. It will save a bunch of memory by using iterators instead of conversion to list and allow you to work on huge files.