Una calculadora sencilla

def calculator(operation, a, b):
  if operation == 'add' || operation == '+':
    return a + b
  elif operation == 'subtract' || operation == '-':
    return a - b
  elif operation == 'multiply' || operation == '*':
    return a * b
  elif operation == 'divide' || operation == '//':
    return a // b
    
calculator('add', 1, 2)