docstr: Add a new container around obj
code: def addContainer(self, typ, obj):
      """Add a new container around obj"""
      new = self.makeContainer(typ)
  
      container = self.getContainer(obj)
      container.insert(new, "before", obj)
      # print "Add container:", new, " -> ", container
      if obj is not None:
          new.insert(obj)
      self.dockdrop.raiseOverlay()
      return new
  
imports: import weakref
  from ..Qt import QtWidgets
  from .Container import Container, HContainer, TContainer, VContainer
  from .Dock import Dock
  from .DockDrop import DockDrop
label_desc: Use image node_id 7 for calling the DockArea obj's underlying member method code with example usage: obj.addContainer(typ, obj) and returns: new