docstr: Approximate current-flow betweenness centrality: solvers
docstr_tok: ["Approximate","current-flow","betweenness","centrality",":","solvers"]
code: def test_solvers(self):
      "Approximate current-flow betweenness centrality: solvers"
      G = nx.complete_graph(4)
      epsilon = 0.1
      for solver in ["full", "lu", "cg"]:
          b = approximate_cfbc(
              G, normalized=False, solver=solver, epsilon=0.5 * epsilon
          )
          b_answer = {0: 0.75, 1: 0.75, 2: 0.75, 3: 0.75}
          for n in sorted(G):
              np.testing.assert_allclose(
                  b[n], b_answer[n], atol=epsilon
              )
  
imports: import pytest
  import networkx
  from networkx import approximate_current_flow_betweenness_centrality
  from networkx import edge_current_flow_betweenness_centrality
label_desc: Use image node_id 6 for calling the TestApproximateFlowBetweennessCentrality obj's underlying member method code with example usage: obj.test_solvers() without return types