code: def test_output_shape_is_correct(self):
      processor = processors.Mix(name="mix")
      x1 = np.zeros((2, 100, 3), dtype=np.float32) + 1.0
      x2 = np.zeros((2, 100, 3), dtype=np.float32) + 2.0
      mix_level = (
          np.zeros((2, 100, 1), dtype=np.float32) + 0.1
      )  # will be passed to sigmoid
  
      output = processor(x1, x2, mix_level)
  
      self.assertListEqual([2, 100, 3], output.shape.as_list())
  
file_path: ddsp/ddsp/processors_test.py
imports: from absl.testing import parameterized
  from ddsp import core
  from ddsp import effects
  from ddsp import processors
  from ddsp import synths
  import numpy
  import tensorflow.compat.v2
label_desc: Use image node_id 1 for calling the MixTest obj's underlying member method code with example usage: obj.test_output_shape_is_correct() without return types