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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 serialize(self, m):
        '''Serialize the macaroon in JSON format indicated by the version field.

        @param macaroon the macaroon to serialize.
        @return JSON macaroon.
        '''
        from pymacaroons import macaroon
        if m.version == macaroon.MACAROON_V1:
            return self._serialize_v1(m)
        return self._serialize_v2(m)