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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def __diff_set(self, level):
 """Difference of sets"""

        t1_hashtable = self.__create_hashtable(level.t1, level)
        t2_hashtable = self.__create_hashtable(level.t2, level)

        t1_hashes = set(t1_hashtable.keys())
        t2_hashes = set(t2_hashtable.keys())

        hashes_added = t2_hashes - t1_hashes
        hashes_removed = t1_hashes - t2_hashes

        items_added = [t2_hashtable[i].item for i in hashes_added]
        items_removed = [t1_hashtable[i].item for i in hashes_removed]

        for item in items_added:
            change_level = level.branch_deeper(
                notpresent, item, child_relationship_class=SetRelationship)
            self.__report_result('set_item_added', change_level)

        for item in items_removed:
            change_level = level.branch_deeper(
                item, notpresent, child_relationship_class=SetRelationship)
            self.__report_result('set_item_removed', change_level)