code: def wellek_to_f2(eps, n_groups):
      """Convert Wellek's effect size (sqrt) to Cohen's f-squared
  
      This computes the following effect size :
  
         f2 = 1 / n_groups * eps**2
  
      Parameters
      ----------
      eps : float or ndarray
          Wellek's effect size used in anova equivalence test
      n_groups : int
          Number of groups in oneway comparison
  
      Returns
      -------
      f2 : effect size Cohen's f-squared
  
      """
      f2 = 1 / n_groups * eps**2
      return f2
  
imports: import numpy
  from scipy import stats
  from scipy.special import ncfdtrinc
  from statsmodels.stats.power import ncf_cdf, ncf_ppf
  from statsmodels.stats.robust_compare import TrimmedMean, scale_transform
  from statsmodels.tools.testing import Holder
  from statsmodels.stats.base import HolderTuple
label_desc: Use image node_id 4 for calling a global function with example usage: wellek_to_f2(eps, n_groups) and returns: f2