code: def test_osrt(self):
      df = DataFrame(
          dict(zip(["a", "b", "c"], self.df_bn.tolist()))
      ).melt()
      p, _, _ = som.test_osrt(df, val_col="value", group_col="variable")
      result = 0.3157646
      self.assertTrue(np.allclose(p, result, atol=1.0e-3))
  
imports: import os
  import sys
  import unittest
  import matplotlib
  import scikit_posthocs._posthocs
  import scikit_posthocs._omnibus
  import scikit_posthocs._outliers
  import scikit_posthocs._plotting
  import scikit_posthocs._global
  import seaborn
  import numpy
  import matplotlib.axes
  from pandas import DataFrame, Series
label_desc: Use image node_id 18 for calling the TestPosthocs obj's underlying member method code with example usage: obj.test_osrt() without return types