class_docstr: Test class for scipy.stats.variation
code: def test_2d_size_zero_with_axis(self, axis, expected):
      x = np.empty((3, 0))
      y = variation(x, axis=axis)
      assert_equal(y, expected)
  
imports: import numpy
  from numpy.testing import assert_equal, assert_allclose
  import pytest
  from scipy.stats import variation
  from scipy._lib._util import AxisError
label_desc: Use image node_id 15 for calling the TestVariation obj's underlying member method code with example usage: obj.test_2d_size_zero_with_axis(axis, expected) without return types