class_docstr: Unit tests for the
  :func:`~networkx.generators.directed.random_k_out_graph` function.
class_docstr_tok: ["Unit","tests","for","the",":","func",":","`","~networkx.generators.directed.random_k_out_graph","`","function","."]
code: def test_negative_alpha(self):
      with pytest.raises(ValueError, match="alpha must be positive"):
          random_k_out_graph(10, 3, -1)
  
file_path: networkx/networkx/generators/tests/test_directed.py
imports: import pytest
  import networkx
  from networkx.classes import Graph, MultiDiGraph
  from networkx.generators.directed import gn_graph, gnc_graph, gnr_graph, random_k_out_graph, random_uniform_k_out_graph, scale_free_graph
label_desc: Use image node_id 3 for calling the TestRandomKOutGraph obj's underlying member method code with example usage: obj.test_negative_alpha() without return types