code: def test_chromatic_polynomial_disjoint(G):
      """Chromatic polynomial factors into the Chromatic polynomials of its
      components. Verify this property with the disjoint union of two copies of
      the input graph.
      """
      x_g = nx.chromatic_polynomial(G)
      H = nx.disjoint_union(G, G)
      x_h = nx.chromatic_polynomial(H)
      assert sympy.simplify(x_g * x_g).equals(x_h)
  
imports: import pytest
  import networkx
label_desc: Use image node_id 4 for calling a global function with example usage: test_chromatic_polynomial_disjoint(G) without return types