code: def move_group(self, group, parent, index=None):
          
          if not isinstance(group, Group):
              raise TypeError("group param must be of type Group")
          
          if parent is not None and not isinstance(parent, Group):
              raise TypeError("parent param must be of type Group")
              
          if group is parent:
              raise ValueError("group and parent are the same")
              
          if parent is None:
              parent = self.root
          elif parent not in self.groups:
              raise exc.UnboundModelError("Parent group doesn't exist / is not bound to this database.")
              
          if group not in self.groups:
              raise exc.UnboundModelError("Group doesn't exist / is not bound to this database.")
          
          curr_parent = group.parent
          curr_parent.children.remove(group)
          
          if index is None:
              parent.children.append(group)
              self.log.debug("Moving {0!r} to child of {1!r}, (appending)".format(group, parent))
          else:
              parent.children.insert(index, group)
              self.log.debug("Moving {0!r} to child of {1!r}, (at position {2!r})".format(group, parent, index))
          
          #Recurse down and reset level of all moved nodes
          def set_level(g):
              g.level = g.parent.level + 1
              for child in g.children:
                  set_level(child)
  
          group.parent = parent
          set_level(group)
          group.modified = util.now()
          
          self._rebuild_groups()
docs: Move group to be a child of new parent.
          
          :param group: The group to move.
          :type group: :class:`keepassdb.model.Group`
          :param parent: The new parent for the group.
          :type parent: :class:`keepassdb.model.Group`
          :param index: The 0-based index within the parent (defaults to appending
                        group to end of parent's children).
          :type index: int