bagels | Python Fiddle

import random
def getSecretNum(numDigits):
    # Returns a string that is numDigits long, made up of unique random digits.
    numbers = list(range(10))
    random.shuffle(numbers)
    secretNum = ''
    for i in range(numDigits):
        secretNum += str(numbers[i])
    return secretNum

def getClues(guess, secretNum):
    # Returns a string with the pico, fermi, bagels clues to the user.
    if guess == secretNum:
        return 'You got it!'

clue = []

for i in range(len(guess)):
        if guess[i] == secretNum[i]:
            clue.append('Fermi')
        elif guess[i] in secretNum:
            clue.append('Pico')
    if len(clue) == 0:
        return 'Bagels'

clue.sort()
    return ' '.join(clue)

def isOnlyDigits(num):
    # Returns True if num is a string made up only of digits. Otherwise returns False.
    if num == '':
        return False

for i in num:
        if i not in '0 1 2 3 4 5 6 7 8 9'.split():
            return False

return True

def playAgain():
    # This function returns True if the player wants to play again, otherwise it returns False.
    print('Do you want to play again? (yes or no)')
    return input().lower().startswith('y')

NUMDIGITS = 3
MAXGUESS = 10

print('I am thinking of a %s-digit number. Try to guess what it is.' % (NUMDIGITS))
print('Here are some clues:')
print('When I say:    That means:')
print('  Pico         One digit is correct but in the wrong position.')
print('  Fermi        One digit is correct and in the right position.')
print('  Bagels       No digit is correct.')

while True:
    secretNum = getSecretNum(NUMDIGITS)
    print('I have thought up a number. You have %s guesses to get it.' % (MAXGUESS))

numGuesses = 1
    while numGuesses <= MAXGUESS:
        guess = ''
        while len(guess) != NUMDIGITS or not isOnlyDigits(guess):
            print('Guess #%s: ' % (numGuesses))
            guess = input()

clue = getClues(guess, secretNum)
        print(clue)
        numGuesses += 1

if guess == secretNum:
            break
        if numGuesses > MAXGUESS:
            print('You ran out of guesses. The answer was %s.' % (secretNum))

if not playAgain():
        break

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