code: def test_row_stack(self, xp, dtype1, dtype2):
      a = testing.shaped_arange((4, 3), xp, dtype1)
      b = testing.shaped_arange((3,), xp, dtype2)
      c = testing.shaped_arange((2, 3), xp, dtype1)
      return xp.row_stack((a, b, c))
  
imports: import numpy
  import pytest
  import cupy
  from cupy import testing
  from cupy import cuda
label_desc: Use image node_id 61 for calling the TestJoin obj's underlying member method code with example usage: obj.test_row_stack(xp, dtype1, dtype2) and returns: xp