code: def test_mass(self):
      a = np.array([0.0, 1.0, 1.0, 0.0])
      b = np.array([0.0, 4.0, 4.0, 0.0])
  
      outcome = np.array([0.0])
  
      assert np.allclose(np.sqrt(mass(a, b)), outcome)
  
imports: from matrixprofile.utils import *
  import numpy
  import pytest
label_desc: Use image node_id 13 for calling the TestClass obj's underlying member method code with example usage: obj.test_mass() without return types