computer chooses a number between 1 and 100 randomly and you have to guess it. Python

guess_number.py

#in this game computer choses a number between 1 and 100 randomly and you have to guess it
import random



def is_valid_num(s):
    if s.isdigit() and 1 <= int(s) <= 100:
        return True
    else:
        return False;
    
    
    
def main():
    rand_num = random.randint(1,100)
   # print rand_num
    guessed_number = False
    guess = str(raw_input('please input your guess between 1 and 100  '))
    num_of_guess = 0
    while not guessed_number:
        if not is_valid_num(guess) :
            guess = str(input('please input only digits  enter   again pls    '))
            continue
        else:
            num_of_guess += 1
            guess = int(guess)
            
        if guess < rand_num :
            guess = str(input('your number is small  again pls    '))
        elif guess > rand_num :
            guess = str(input('your number is bigger  again pls    '))
        else :
            print 'you find the number in  ', num_of_guess ,'times'
            guessed_number = True
    print 'thank you for playing'
    
    
    
main()

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