+--------------+
      | containerN   |
    +--------------+ |
    |  container2  | |
   +-------------+ | | 
   |  container1 | | | 
   |             | | |
   |  +-------+  | | |
   |  | part  |  | | |
   |  +-------+  | |-+ 
   |             |-+  
   +-------------+