Your approach needs some debugging as it's not 100% correct yet, but this current mistake is probably due to the fact that you are not returning anything - replace print(number) by return(number) at the end of your solution.
print(number)
return(number)
Loading collection data...
Your approach needs some debugging as it's not 100% correct yet, but this current mistake is probably due to the fact that you are not returning anything - replace
print(number)
byreturn(number)
at the end of your solution.