I'm getting an error, please help! thanks

[CabbageMan]

If you want to reassign the 'starting_crate_num' variable, you need to specify that you want to use the variable from outside the function.
You do this by writing the variable name in the parentheses.

starting_crate_num = 0

def start(starting_crate_num):
    starting_crate_num += 1