code: def test_oneovertwon(self):
      # Check derivative at x=1/2n  (Discontinuous at x=1/n, so check at x=1/2n)
      n = np.arange(1, 20)
      x = 1.0 / 2 / n
      pp = -(n * x + 1) * (1 + x) ** (n - 2)
      dataset0 = np.column_stack([n, x, pp])
      FuncData(_smirnovp, dataset0, (0, 1), 2, rtol=_rtol).check(
          dtypes=[int, float, float]
      )
  
imports: import itertools
  import sys
  import pytest
  import numpy
  from numpy.testing import assert_
  from scipy.special._testutils import FuncData
  from scipy.special import kolmogorov, kolmogi, smirnov, smirnovi
  from scipy.special._ufuncs import _kolmogc, _kolmogci, _kolmogp, _smirnovc, _smirnovci, _smirnovp
label_desc: Use image node_id 4 for calling the TestSmirnovp obj's underlying member method code with example usage: obj.test_oneovertwon() without return types