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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 case(self, size, kw, *parameters):
 """An element inside a bag started with `Start Bag`. The first argument is size which can be absolute value like `1`, a range like `0-3`, or just `*` to accept any number of elements. Examples: | Start bag | intBag | | case | 0-1 | u8 | foo | 42 | | case | 0-2 | u8 | bar | 1 | | End bag | """

        # TODO: check we are inside a bag!
        self._start_bag_case(size)
        BuiltIn().run_keyword(kw, *parameters)
        self._end_bag_case()