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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(self, url_type):
 """ Accepts either 'public' or 'private' as a parameter, and returns the corresponding value for 'public_url' or 'private_url', respectively. """

        lowtype = url_type.lower()
        if lowtype == "public":
            return self.public_url
        elif lowtype == "private":
            return self.private_url
        else:
            raise ValueError("Valid values are 'public' or 'private'; "
                    "received '%s'." % url_type)