[Python] functions help

[TheLaughingMan]

So it is late and i am trying to find this issue out with this code for my class. Anyone that can help, I would so need right now.

hear is the code:

import random
import time


def get_letter_grade(percentage):
if percentage >= 95:
letter_grade = "A"
return (letter_grade)
if percentage >= 94:
letter_grade = "A-"
if percentage >= 91:
letter_grade = "B+"
if percentage >= 88:
letter_grade = "B"
if percentage >= 85:
letter_grade = "B-"
if percentage >= 82:
letter_grade = "C+"
if percentage >= 79:
letter_grade = "C"
if percentage >= 76:
letter_grade = "C-"
if percentage >= 73:
letter_grade = "D+"
if percentage >= 70:
letter_grade = "D"
if percentage >= 67:
letter_grade = "D-"
if percentage >= 65:
letter_grade = "F"

return (letter_grade)

def get_grade_number(grade):
grade = int(grade)
get_letter_grade()

def opt(grade,percentage):
opt = int(get_letter_grade,get_grade_number)
return (letter_grade)


grade = 0

def menu():
print ("1: Enter grade in percentage (0-100)")
print ("2: Get letter grade from percentage grade")
print ("3: Calculate letter from extra credit")
print ("4: Calculate extra credit needed to boost letter grade")
print ("0: Exit ")
print (("Current Grade:"),(grade))


loop = 1

while loop ==1:
choice = menu()
choice = input ("Please make a choice: ")
choice = int(choice)

if choice == 1:
grade = input(" Enter percentage grade (0-100)?:")

elif choice == 2:
percentage = (opt)
opt =((get_letter_grade,get_grade_number), print (percentage))


basicly it a menu thing seen on this video :http://www.screencast.com/t/ZonV3w5Y7

but I am stuck at the part were trying to get the grade letter within the code.

I do not knwo what i am doing wrong with it so any help I baddly need.

Not sure how to do the when u get the % grade trying to get elif choice == 2 to work when it displays the letter grade.

thoughts on this?