class_docstr: Unit tests for the
  :func:`~networkx.algorithms.matching.max_weight_matching` function.
code: def test_single_edge(self):
      G = nx.Graph()
      G.add_edge(0, 1)
      assert edges_equal(
          nx.max_weight_matching(G), matching_dict_to_set({0: 1, 1: 0})
      )
      assert edges_equal(
          nx.min_weight_matching(G), matching_dict_to_set({0: 1, 1: 0})
      )
  
imports: import math
  from itertools import permutations
  from pytest import raises
  import networkx
  from networkx.algorithms.matching import matching_dict_to_set
  from networkx.utils import edges_equal
label_desc: Use image node_id 3 for calling the TestMaxWeightMatching obj's underlying member method code with example usage: obj.test_single_edge() without return types