code: def __init__(self, d: Mapping):
      self.d = d
  
imports: from __future__ import annotations
  import heapq
  import operator
  import pickle
  import random
  from collections.abc import Mapping
  import pytest
  from distributed.collections import LRU, HeapSet, sum_mappings
label_desc: Use image node_id 1 to create a new ReadOnlyMapping object from inherited base classes: Mapping with example: obj = ReadOnlyMapping(d)