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