code: def test_nanmean_float16(self, xp):
      a = testing.shaped_arange((2, 3), xp, numpy.float16)
      a[0][0] = xp.nan
      return xp.nanmean(a)
  
imports: import math
  import numpy
  import pytest
  import cupy
  from cupy import testing
label_desc: Use image node_id 3 for calling the TestNanMeanAdditional obj's underlying member method code with example usage: obj.test_nanmean_float16(xp) and returns: xp