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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 block_account(self, hash):
 """ Returns the account containing block :param hash: Hash of the block to return account for :type hash: str :raises: :py:exc:`nano.rpc.RPCException` "xrb_3e3j5tkog48pnny9dmfzj1r16pg8t1e76dz5tmac6iq689wyjfpi00000000" """


        hash = self._process_value(hash, 'block')

        payload = {"hash": hash}

        resp = self.call('block_account', payload)

        return resp['account']