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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 add(self, elem):
 """Adds a JWK object to the set :param elem: the JWK object to add. :raises TypeError: if the object is not a JWK. """

        if not isinstance(elem, JWK):
            raise TypeError('Only JWK objects are valid elements')
        set.add(self, elem)