code: def fulfill(self, agreement_id, document_id, grantee_address, account):
          
          return self._fulfill(
              agreement_id,
              document_id,
              grantee_address,
              transact={'from': account.address,
                        'passphrase': account.password}
          )
docs: Fulfill the access secret store condition.
  
          :param agreement_id: id of the agreement, hex str
          :param document_id: refers to the DID in which secret store will issue the decryption
          keys, DID
          :param grantee_address: is the address of the granted user, str
          :param account: Account instance
          :return: true if the condition was successfully fulfilled, bool