def collatz(number):  
    
    if number == 0:
        try:
            print('enter a number:')
            number=int(input())
            print("your number is " + str(number))
        except ValueError:
            print("enter an integer")
    
    if number == 1:
        print("the number is now 1")
    
    if number > 1:
        #if number is even
        if number%2 == 0:
            print("this is an even number")
            #print number//2
            number = number//2
            print("divided by two, is " + str(number))
            #re-run on this new number
            collatz(int(number))
    
        else:
            print("this is an odd number, but is not 1")
            number = ((number*3)+1)
            print("times 3, plus one, is " + str(number))
            #re-run on this new number
            collatz(int(number))

collatz(0)

enter a number:
pupu$$$
enter an integer