code: def test_imperative_pf():
      import nnabla.parametric_functions as PF
  
      x = nn.NdArray([2, 3, 4, 5])
      y = PF.batch_normalization(x)
  
imports: import numpy
  import nnabla
  from nnabla.testing import assert_allclose
label_desc: Use image node_id 3 for calling a global function with example usage: test_imperative_pf() without return types