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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 child_cardinality(self, child):
 """ Return the cardinality of a child element :param child: The name of the child element :return: The cardinality as a 2-tuple (min, max). The max value is either a number or the string "unbounded". The min value is always a number. """

        for prop, klassdef in self.c_children.values():
            if child == prop:
                if isinstance(klassdef, list):
                    try:
                        _min = self.c_cardinality["min"]
                    except KeyError:
                        _min = 1
                    try:
                        _max = self.c_cardinality["max"]
                    except KeyError:
                        _max = "unbounded"

                    return _min, _max
                else:
                    return 1, 1
        return None