code: def test_modf(self, xp, dtype):
      a = xp.array([-2.5, -1.5, -0.5, 0, 0.5, 1.5, 2.5], dtype=dtype)
      b, c = xp.modf(a)
      d = xp.empty((2, 7), dtype=dtype)
      d[0] = b
      d[1] = c
      return d
  
imports: import itertools
  import warnings
  import numpy
  import pytest
  import cupy
  from cupy import testing
label_desc: Use image node_id 1 for calling the TestArithmeticModf obj's underlying member method code with example usage: obj.test_modf(xp, dtype) and returns: d