Guesses a number that you think of

No_Guess_2.py

#Number Guesser 2
print("Think of a number between 1 and 100.")

def checker(guess):
    nums = [1,2,3]
    print("Number is "+ str(guess) + ". Is my answer:")
    print("[1] correct")
    print("[2] Too high")
    print("[3] Too low")
    while True:
        try:
           response = int(input())
           if response in nums:
               break
           else:
               print("Enter [1] [2] or [3]!")
        except ValueError:
           print("Enter [1] [2] or [3]!")
    return response

#Initial guess and limits
guess = 50
high = 100
low = 1
counter = 0

while True:
    response = checker(guess)
    counter += 1
    if response == 1:
        print("I Win! I took " + str(counter) + " attempts!")
        break
    elif response == 2:
        high = guess
    else:
        low = guess
    guess = int((high + low)/2)