UnboundLocalError: local variable ' ' referenced before assignment

[d3fi]

one thing I think is wrong is left = weight % 5
Do you know what modulo operator does?

I am not sure. I got help from an earlier post with the "%".

i want the program to findt the nearest 5. exampe. weight can not be 16.
so how I understood it was. 16 % 5 = 1 (count with your fingers 5 - 10 - 15.. 3 times, how much is left = 1)
and then you say 16(the weight)-(16 % 5) = 15

is that right?

How else could i write it? :)