The best design pattern for collecting objects

Question

I have the following architecture:

         +-----------------+
         |   Collection    |
         |                 |
         |                 |
         |                 |
         |                 |
         +-----------------+
           |        ^
           |        |
  Create() |        |
           |        |
           v        | GetItem(B)
+------------+      |
|   Item A   |      |
|            |      |
|            +------+
|            |
+------------+

A class that manages a set of elements creates elements. And these items may need other items from the collection.

The actual code is in python, and so far Collectionpasses itself as a parameter to the generated one Item. As I see it, this is bad practice. The only improvement that I see is to pass in a few functions Collectionneeded for Item, instead of the whole instance.

For instance:

class Collection:
    GetItem(self, id):
        ...
    CreateItem(self, id):
        item = Item(id, self) # <-- pass self
        ...

class Item:
    __init__(self, id, col):
        ...
        col.GetItem(...)

How can I avoid passing self as a parameter? Or is this common use in Python?

More detailed example

 ┌──────┐            ┌──────────┐           ┌─────┐                              
 │Client│            │Collection│           │ItemA│                              
 └──┬───┘            └────┬─────┘           └──┬──┘                              
    │ UpdateItem(A, param)│                    │                                 
    │ ────────────────────>                    │                                 
    │                     │                    │                                 
    │                     │ Update(param, self)│  ╔═════════════════════════════╗
    │                     │ ───────────────────>  ║Need to update linked ItemB ░║
    │                     │                    │  ╚═════════════════════════════╝
    │                     │     GetItem(B)     │                                 
    │                     │ <───────────────────                                 
    │                     │                    │                                 
    │                     │        ItemB       │                                 
    │                     │  ─ ─ ─ ─ ─ ─ ─ ─ ─ >                                 
    │                     │                    │                                 
    │                     │                    │────┐                            
    │                     │                    │    │ UpdateItemB()              
    │                     │                    │<───┘                            
 ┌──┴───┐            ┌────┴─────┐           ┌──┴──┐                              
 │Client│            │Collection│           │ItemA│                              
 └──────┘            └──────────┘           └─────┘                              

Answer 1

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Answer 2

, : https://sourcemaking.com/design_patterns/composite

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