code: def y_only(y):
      cosy = np.cos(y)
      siny = np.sin(y)
      return np.array(
          [
              [cosy, 0, siny],
              [0, 1, 0],
              [-siny, 0, cosy],
          ]
      )
  
file_path: nibabel/nibabel/tests/test_euler.py
imports: import math
  import numpy
  import pytest
  from numpy import pi
  from numpy.testing import assert_array_almost_equal, assert_array_equal
  from ..None import eulerangles
  from ..None import quaternions
label_desc: Use image node_id 2 for calling a global function with example usage: y_only(y) and returns: np