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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 next_builder(self):
 """Create a new builder based off of this one with its sequence number incremented. :return: A new Builder instance :rtype: :class:`Builder` """

        sequence = self.sequence + 1
        next_builder = Builder(
            horizon_uri=self.horizon.horizon_uri,
            address=self.address,
            network=self.network,
            sequence=sequence,
            fee=self.fee)
        next_builder.keypair = self.keypair
        return next_builder