code: def _compile_bus_injection(self):
          
          string = '"""\n'
          for device, series in zip(self.devices, self.series):
              if series:
                  string += 'system.' + device + '.gcall(system.dae)\n'
          string += '\n'
          string += 'system.dae.reset_small_g()\n'
          string += self.gisland
          string += '"""'
          self.bus_injection = compile(eval(string), '', 'exec')
docs: Impose injections on buses