code: def test_find_best_tree_smoke(num_edges, backend):
      pyro.set_rng_seed(num_edges)
      E = num_edges
      V = 1 + E
      K = V * (V - 1) // 2
      for _ in range(10 if backend == "cpp" or num_edges <= 30 else 1):
          edge_logits = torch.rand(K)
          find_best_tree(edge_logits, backend=backend)
  
file_path: pyro/tests/distributions/test_spanning_tree.py
imports: import logging
  import os
  from collections import Counter
  import pytest
  import torch
  import pyro
  from pyro.distributions.spanning_tree import NUM_SPANNING_TREES, SpanningTree, find_best_tree, make_complete_graph, sample_tree
  from tests.common import assert_equal, xfail_if_not_implemented
label_desc: Use image node_id 4 for calling a global function with example usage: test_find_best_tree_smoke(num_edges, backend) without return types