Create module, then import said module

Question

I am trying to create a module and import it into another program. My task for the module is for it to:

• accept a string
• have a docstring explaining what it does
• return the count of how many letters are in the string parameter

I was able to create the module, and I think it should return the correct count, but I am either having trouble implementing it into my original code, or the code in my new module file is wrong as well.

Here is the code from the original file:

# Program for Determining Palindromes
import stack
import letterCount
from letterCount import countLetters
# welcome
print ('This program can determine if a given string is a palindrome\n')
print ('(Enter return to exit)')
# init
char_stack = stack.getStack()
empty_string = ''
# get string from user
chars = input('Enter string to check: ')
while chars != empty_string:
 if len(chars) == 1:
 print('A one letter word is by definition a palindrome\n')
 else:
 # init
 is_palindrome = True
 # determine half of length. excluding any middle character
 compare_length = len(chars) // 2
 # push second half of input string on stack
 for k in range(compare_length, len(chars)):
 stack.push(char_stack, chars[k])
 # pop chars and compare to first half of string
 k = 0
 while k < compare_length and is_palindrome:
 ch = stack.pop(char_stack)
 if chars[k].lower() != ch.lower():
 is_palindrome = False
 k = k + 1
 # display results
 if is_palindrome:
 print (chars, 'is a palindrome\n')
 print (
 else:
 print (chars, 'is NOT a palindrome\n')
 # get string from user
 chars = input('Enter string to check: ')

and here is the code for the module I created:

def countLetters(chars):
 """this function keeps track of the longest palindrome"""
 palinlen = len(chars)
 print("This Palindrome is ",palinlen," characters long!")

What exactly am I missing? Any help would be greatly appreciated!

• Maria Nazari: I'm not sure what your actual issue is, but you can use letterCount.countLetters('enter your string here')
• BruceWayne: Why do you think you're having trouble? Do you get errors? Do you get unexpected output?
• glotchimo: If you have a traceback, please provide.
• G. Anderson: You never call countLetters after importing it, which means that you never invoke it. Pedantically, the function/module itself technically doesn't return anything, it only does a print(), when you say you want it to return. Also, according to PEP guidelines, functions should be named using snake_case, all lowercase with underscores, not mixed case like you have

Answer 1

You fail to actually call the function you have imported.

The comments on your question already explain this, but to go into a little more detail:

Say we have 2 files, one is my 'module', the other my project (this is a useless example btw)

#Module file, moduleFoo.py
def foo(bar):
 print(bar)

.

#Project file
import moduleFoo
moduleFoo.foo("Some wild stuff")

With the final line of our project file, we call or invoke our function inside the module file

This can also be done doing:

from moduleFoo import foo
foo("Some wild stuff")