Suggest how to make the following Python loop execute faster.
def find_list_difference(list1, list2):
    diff = []
    for item in list1:
        if item not in list2:
            diff.append(item)
    return diff
def find_list_difference(list1, list2):
    diff = []
    list2_set = set(list2)
    for item in list1:
        if item not in list2_set:
            diff.append(item)
    return diff