code: def test_CommaOperator():
      expr = CommaOperator(PreIncrement(x), 2 * x)
      assert ccode(expr) == "(++(x), 2*x)"
      assert expr.func(*expr.args) == expr
  
file_path: sympy/sympy/codegen/tests/test_cnodes.py
imports: from sympy.core.symbol import symbols
  from sympy.printing.codeprinter import ccode
  from sympy.codegen.ast import Declaration, Variable, float64, int64, String, CodeBlock
  from sympy.codegen.cnodes import alignof, CommaOperator, goto, Label, PreDecrement, PostDecrement, PreIncrement, PostIncrement, sizeof, union, struct
label_desc: Use image node_id 2 for calling a global function with example usage: test_CommaOperator() without return types