code: def test_add_const_simplify(self):
      expr = (
          "#Add",
          ("#Mul", (1.5, ("#CPow1.2000e+00", ("#x",)))),
          ("#Mul", (1.2,), (7,)),
      )
      did_something, new_expr = add_const_simplify(expr)
      self.assertTrue(did_something)
      self.assertEqual(
          new_expr,
          ("#Add", ("#Mul", (1.5, ("#CPow1.2000e+00", ("#x",))))),
      )
      did_something, new_expr = add_const_simplify(new_expr)
      self.assertFalse(did_something)
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import edward
  import numpy
  import tensorflow
  from edward.inferences.conjugacy.simplify import *
  from edward.inferences.conjugacy.simplify import _mul_n
label_desc: Use image node_id 18 for calling the test_simplify_class obj's underlying member method code with example usage: obj.test_add_const_simplify() without return types