def test_float_return_with_float_input_at_nondefault_mean(self):
     self.assertTrue(isinstance(
         utilities.gaussian_density_function(x=0., mu=100), float),
                     msg='Expected float return')
 def test_float_return_with_int_input(self):
     self.assertTrue(isinstance(utilities.gaussian_density_function(x=0),
                                float),
                     msg='Expected float return')