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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 get_session_class(cls, interface_type, resource_class):
 """Return the session class for a given interface type and resource class. :type interface_type: constants.InterfaceType :type resource_class: str :return: Session """

        try:
            return cls._session_classes[(interface_type, resource_class)]
        except KeyError:
            raise ValueError('No class registered for %s, %s' % (interface_type, resource_class))