What does unhashable type: 'Individual' mean for decorators

[Bobby Renecker]

Trying to figure out why I'm getting the TypeError unhashible type: 'Individual' for my decorator function

Here's the code, the line offspring = func(*args, **kargs) is where i'm getting the error

def mate_constraints(protectedList, protectedValues):

    def decorator(func):

        def wrapper(*args, **kargs):

            offspring = func(*args, **kargs)

       

            offspring = handle_mate_constraints(offspring,protectedList, protectedValues);

            return offspring;

                   

            

        return wrapper;

    return decorator;