_filename is not used
            Args:
                _filename(string)

def output(self, _filename):
        """
            _filename is not used
            Args:
                _filename(string)
        """

        for contract in self.slither.contracts_derived:
            txt = "\nContract %s"%contract.name
            table = PrettyTable(["Function",
                                 "require or assert"])
            for function in contract.functions:
                require = function.all_slithir_operations()
                require = [ir for ir in require if isinstance(ir, SolidityCall) and ir.function in require_or_assert]
                require = [ir.node for ir in require]
                table.add_row([function.name, self._convert([str(m.expression) for m in set(require)])])
            txt += "\n"+str(table)
            self.info(txt)