code: def test_lambda_to_nu():
      assert_equal(sc.lambda2nu(sc.speed_of_light), 1)
  
imports: from __future__ import division, print_function, absolute_import
  from numpy.testing import assert_equal, assert_allclose
  import scipy.constants
label_desc: Use image node_id 2 for calling a global function with example usage: test_lambda_to_nu() without return types