calculator.py

'''
Program : Magical Calculator
Author : Anshul Arya
'''
import re
print("Magical Calculator")
print("Type 'quit' to exit\mn")
previous = 0
run = True

def performMath():
    global run
    global previous
    equation = ""
    
    #if there has been a previous calculation, use that result as the prompt
    if previous == 0:
        equation = input("Enter Equation")
    else:
        equation = input(str(previous))
     
    # if user quit
    if equation =='quit':
        print("Good-Bye :)")
    else:
        equation = re.sub('[a-zA-Z,.:()" "]','',equation)
        if previous == 0:
            previous = eval(equation)
        else:
            previous = eval(str(previous)+ equation)

while run:
    performMath()