code: def adjustChildren(self, delta, secs=False):
          
          if self.adjustmentsBlocked('children'):
              return
              
          if self.itemStyle() != self.ItemStyle.Group:
              return
          
          if not delta:
              return
          
          for c in range(self.childCount()):
              child = self.child(c)
              child.blockAdjustments('range', True)
              if secs:
                  dstart = child.dateTimeStart()
                  dstart = dstart.addSecs(delta)
                  child.setDateStart(dstart.date())
                  child.setTimeStart(dstart.time())
              else:
                  child.setDateStart(child.dateStart().addDays(delta))
              child.blockAdjustments('range', False)
docs: Shifts the children for this item by the inputed number of days.
          
          :param      delta | <int>