code: def test_dropout_forward(self):
      _, y = self.states.forward(None, self.x, self.ratio)
      if self.ratio == 0:
          assert cupy.all(self.x == y)
      else:
          assert cupy.all(self.x != y)
  
imports: import sys
  import numpy
  import pytest
  import cupy
  import cupy.cuda.cudnn
  from cupy import testing
label_desc: Use image node_id 2 for calling the TestCudnnDropout obj's underlying member method code with example usage: obj.test_dropout_forward() without return types