supercalc

import re

print("Johnnys SuperCal")
print("Type quit to exit\n")

previous = 0
run = True

def performMath():
    global run
    global previous
    equation = ""
    if previous == 0:
        equation = input("Enter equation:")
    else:
        equation = input(str(previous))

    if equation == "quit":
        print("Adios human!")
        run = False
    else:
        equation = re.sub('[a-zA-Z,.:()" "]', '', equation)

        if previous == 0:
            previous = eval(equation)
        else:
            previous = eval(str(previous) + equation)

while run:
    performMath()