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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 is_subtype_of(self, type_name, context=None):
 """Whether this class is a subtype of the given type. :param type_name: The name of the type of check against. :type type_name: str :returns: True if this class is a subtype of the given type, False otherwise. :rtype: bool """

        if self.qname() == type_name:
            return True
        for anc in self.ancestors(context=context):
            if anc.qname() == type_name:
                return True
        return False