Python While Loop, the and (&) operator is not working

You should be using the keyword and instead of the bitwise and operator &:

while (v % d != 0) and (u % d != 0): 

This is also the same:

while (v % d) and (u % d): 

Note that & and and will give the same result in the first case, but not in the second.

Your problem though is that you want to use or instead of and. Also your algorithm is highly inefficient. There are better ways to calculate the GCD.