class_docstr: Test flatten_dictionary.
class_docstr_tok: ["Test","flatten_dictionary","."]
code: def _compare(self, observed_output, expected_output):
      assert not any(
          isinstance(o, dict) for o in expected_output.values()
      )
      assert expected_output == observed_output
  
imports: import functools
  import itertools
  import operator
  import random
  import string
  import timeit
  import unittest
  from typing import Iterable, Tuple
  import numpy
  import pytest
  import torch
  from pykeen.utils import _weisfeiler_lehman_iteration, _weisfeiler_lehman_iteration_approx, calculate_broadcasted_elementwise_result_shape, clamp_norm, combine_complex, compact_mapping, compose, estimate_cost_of_sequence, flatten_dictionary, get_optimal_sequence, get_until_first_blank, iter_weisfeiler_lehman, logcumsumexp, project_entity, set_random_seed, split_complex, tensor_product, tensor_sum
label_desc: Use image node_id 4 for calling the FlattenDictionaryTest obj's underlying member method code with example usage: obj._compare(observed_output, expected_output) without return types