code: def _breakdown_point(n_samples, n_subsamples):
      """Approximation of the breakdown point.
  
      Parameters
      ----------
      n_samples : int
          Number of samples.
  
      n_subsamples : int
          Number of subsamples to consider.
  
      Returns
      -------
      breakdown_point : float
          Approximation of breakdown point.
      """
      return (
          1
          - (
              0.5 ** (1 / n_subsamples) * (n_samples - n_subsamples + 1)
              + n_subsamples
              - 1
          )
          / n_samples
      )
  
imports: from __future__ import division, print_function, absolute_import
  import warnings
  from itertools import combinations
  import numpy
  from scipy import linalg
  from scipy.special import binom
  from scipy.linalg.lapack import get_lapack_funcs
  from .base import LinearModel
  from ..base import RegressorMixin
  from ..utils import check_random_state
  from ..utils import check_X_y, _get_n_jobs
  from ..utils.random import choice
  from ..externals.joblib import Parallel, delayed
  from ..externals.six.moves import xrange
  from ..exceptions import ConvergenceWarning
label_desc: Use image node_id 3 for calling a global function with example usage: _breakdown_point(n_samples, n_subsamples) and returns: unknown