Forcing input from pre-defined list.

[metulburr]

What if you wanted to force the input to be a number, and the same again, if not, error message and start again?

https://python-forum.io/Thread-Validating-User-Input

Lastly, can you make the response ignore the capitalisation - so "Multiply" or "multiply" is acceptable?

str.lower() will change your string to all lowercase. Then you only have to compare the lowercase .

how would you make it

I would use dictionaries, not a massive if/elif condition

number1 = int(input("What is the first number?"))
operator = input("What do you want to do + Plus - Minus * Multiply / Divide or p Power of? ")
number2 = int(input("What is the second number?"))

calculate = {
    '+':number1 + number2,
    '-':number1 - number2,
}

print(calculate[operator])