code: def forward(self):
      self.dot = np.sum(self.a * self.b, -1)
      self.a_sqrt = np.sqrt(np.sum(np.square(self.a), -1) + 1e-9)
      self.b_sqrt = np.sqrt(np.sum(np.square(self.b), -1) + 1e-9)
      self.sim = self.dot / (self.a_sqrt * self.b_sqrt)
      return self.sim
  
file_path: CNTK/bindings/python/cntk/losses/tests/cosine_distance_test.py
imports: import numpy
  import pytest
  import cntk
label_desc: Use image node_id 2 for calling the numpy_cos obj's underlying member method code with example usage: obj.forward() and returns: self