cant understand the logic behind shorthand form of operator

[jefsummers]

This gets a little deep, but you need to read about inplace operators in the Python docs. The problem is that the assignment to Reverse (btw - don't use capitals for the first letter in variable names, see PEP 8) occurs BEFORE the addition. So, it stays 0. If you then separate the operations it works.

Number=123
Reverse = 0    
while(Number > 0):    
    Reminder = Number %10    
    Reverse*=10
    Reverse+=Reminder
    print(Reverse)    
    Number = Number //10   
print(Reverse)

Output:
3
32
321
321