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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 generate_element_class(tuple_instance):
 """Dynamically create a sub-class of PREMISElement given ``tuple_instance``, which is a tuple representing an XML data structure. """

    schema = tuple_to_schema(tuple_instance)

    def defaults(self):
        return {}

    def schema_getter(self):
        return schema

    new_class_name = "PREMIS{}Element".format(schema[0].capitalize())
    return type(
        new_class_name,
        (PREMISElement,),
        {"defaults": property(defaults), "schema": property(schema_getter)},
    )