docs: def move_group_in_parent(self, group = None, index = None):
          """Move group to another position in group's parent.
          
          index must be a valid index of group.parent.groups
  
          """
          
          if group is None or index is None:
              raise KPError("group and index must be set")
          elif type(group) is not v1Group or type(index) is not int:
              raise KPError("group must be a v1Group-instance and index "
                            "must be an integer.")
          elif group not in self.groups:
              raise KPError("Given group doesn't exist")
          elif index < 0 or index >= len(group.parent.children):
              raise KPError("index must be a valid index if group.parent.groups")
          else:
              group_at_index = group.parent.children[index]
              pos_in_parent = group.parent.children.index(group) 
              pos_in_groups = self.groups.index(group)
              pos_in_groups2 = self.groups.index(group_at_index)
  
              group.parent.children[index] = group
              group.parent.children[pos_in_parent] = group_at_index
              self.groups[pos_in_groups2] = group
              self.groups[pos_in_groups] = group_at_index
              if group.children:
                  self._move_group_helper(group)
              if group_at_index.children:
                  self._move_group_helper(group_at_index)
              group.last_mod = datetime.now().replace(microsecond=0)
              return True