code: def _construct(self, targets, control_flow_slice=False):
          
  
          if control_flow_slice:
              simruns = [ r for r, _ in targets ]
              self._construct_control_flow_slice(simruns)
  
          else:
              self._construct_default(targets)
docs: Construct a dependency graph based on given parameters.
  
          :param targets:             A list of tuples like (CFGNode, statement ID)
          :param control_flow_slice:  Is the backward slicing only depends on CFG or not.