@classmethod
def unregister_term_class(cls, term_name):
    """
        Remove a registration previously made with :py:method:`TermParser.register_term_class`

        :param term_name: Fully-qualified term name. Will be converted to lowercase.
        :return:
        """
    try:
        del cls.term_classes[term_name.lower()]
    except KeyError:
        pass
