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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 relativize(self, origin):
 """If self is a subdomain of origin, return a new name which is self relative to origin. Otherwise return self. @rtype: dns.name.Name object """


        if not origin is None and self.is_subdomain(origin):
            return Name(self[: -len(origin)])
        else:
            return self