code: def test_associative():
      c1 = C("Add", (1, 2, 3))
      c2 = C("Add", (x, y))
      assert tuple(unify(c1, c2, {})) == (
          {x: 1, y: C("Add", (2, 3))},
          {x: C("Add", (1, 2)), y: 3},
      )
  
file_path: sympy/sympy/unify/tests/test_unify.py
imports: from sympy.unify.core import Compound, Variable, CondVariable, allcombinations
  from sympy.unify import core
label_desc: Use image node_id 6 for calling a global function with example usage: test_associative() without return types