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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_sequence(self):
 """Get the sequence number for a given account via Horizon. :return: The current sequence number for a given account :rtype: int """

        if not self.address:
            raise StellarAddressInvalidError('No address provided.')

        address = self.horizon.account(self.address)
        return int(address.get('sequence'))