Credit organizer, asks for input and returns the based on a query

driver.py

import org
import classes 

#The driver for the program
def main():

    print('This is a college credit organizer')

    #This takes the function and calls it and sets it equal to a variable, I expect either 180 or 120 based on their schools system.
    credits_need = org.CreditsNeeded()

    #This checks to make sure a valid response, I expect if there is no value it exits 
    if credits_need == None:
        pass
    
    #This will ask the series of question that are needed for a "database" and set the dictionary, in this case equal to classes to be used later on. 
    classes = org.get_classes()

    
    

main()

org.py

#Asks user for their schedule to get amount of credits needed.
#This function is needed to be able to calculate the total credits needed to graduate school. I expect it to ask what kind of class(Quarter or Semester and then give a int based on that answer) For example, if quarter is chosen 180 would be the int. 

def CreditsNeeded():
    #sets up a running total
    chances = 0

    #asks user for their school type
    schedule = input('What kind of schedule are you on?(Quarter or Semester): ')
    schedule = schedule.lower()
    

    #Loops to give credits_needs
    while chances < 2:
        if schedule == 'quarter':
            credits_needed = 180
            return credits_needed
        if schedule == 'semester':
            credits_needed = 120
            return credits_needed
        if schedule != 'quarter' and schedule != 'semester':
            print('Error: Invalid option')
            print('Please Try again',end='\n')
            chances += 1
            schedule = input('What kind of schedule are you on?(Quarter or Semester): ')
            schedule = schedule.lower()

    if chances >= 2:
        print('Sorry was not able to process your information')

#creates the class dictionary to track the total credits taken. Not sure if it should use a dictionary 
class_credits = {}


#gets grade  a list for that grade 
#This function is used to ask the general questions I expect it to ask "What grade", "What type" , "What class" and "how many credits its worth"
def get_classes():
    grade = input('What grade is this for?(Enter to exit): ')
    dept = input('What type of class is it?: ')
    Class = input('What class is it?: ')
    credit = input('How many credits is it worth?: ')
   
    
    return class_credits

#creates a helper function for validation        
def validate(x):
    x = x.strip()
    x = x.lower() 
    return x