class_docstr: Nested dict-like object that proxies read and write operations through a root object.
  
  This lets us do synchronous serialization and lazy loading of large values.
class_docstr_tok: ["Nested","dict-like","object","that","proxies","read","and","write","operations","through","a","root","object",".","This","lets","us","do","synchronous","serialization","and","lazy","loading","of","large","values","."]
docstr: Load a value at a particular path from the root.
  
  This should only be implemented by the "_root" child class.
  
  We pass the child_dict so the item can be set on it or not as
  appropriate. Returning None for a nonexistant path wouldn't be
  distinguishable from that path being set to the value None.
docstr_tok: ["Load","a","value","at","a","particular","path","from","the","root",".","This","should","only","be","implemented","by","the","``","_root","''","child","class",".","We","pass","the","child_dict","so","the","item","can","be","set","on","it","or","not","as","appropriate",".","Returning","None","for","a","nonexistant","path","would","n't","be","distinguishable","from","that","path","being","set","to","the","value","None","."]
code: def _root_get(self, path, child_dict):
      """Load a value at a particular path from the root.
  
      This should only be implemented by the "_root" child class.
  
      We pass the child_dict so the item can be set on it or not as
      appropriate. Returning None for a nonexistant path wouldn't be
      distinguishable from that path being set to the value None.
      """
      raise NotImplementedError
  
imports: import json
  import os
  import time
  from wandb_gql import gql
  import wandb
  from wandb import util
  from wandb.apis.internal import Api
  from wandb.sdk import lib
  from wandb.sdk.data_types.utils import val_to_json
label_desc: Use image node_id 4 for calling the SummarySubDict obj's underlying member method code with example usage: obj._root_get(path, child_dict) without return types