code: def __array__(self, dtype=None):
      # Pandas data frames also are array-like: we want to make sure that
      # input validation in cross-validation does not try to call that
      # method.
      return self.array
  
imports: import numpy
  from ..base import BaseEstimator, ClassifierMixin
  from .testing import assert_true
  from .validation import _num_samples, check_array
label_desc: Use image node_id 3 for calling the MockDataFrame obj's underlying member method code with example usage: obj.__array__(dtype) and returns: self