code: def _check_numpy_unicode_bug(labels):
      """Check that user is not subject to an old numpy bug
  
      Fixed in master before 1.7.0:
  
        https://github.com/numpy/numpy/pull/243
  
      """
      if np_version[:3] < (1, 7, 0) and labels.dtype.kind == "U":
          raise RuntimeError(
              "NumPy < 1.7.0 does not implement searchsorted"
              " on unicode data correctly. Please upgrade"
              " NumPy to use LabelEncoder with unicode inputs."
          )
  
imports: from collections import defaultdict
  import itertools
  import array
  import numpy
  import scipy.sparse
  from ..base import BaseEstimator, TransformerMixin
  from ..utils.fixes import np_version
  from ..utils.fixes import sparse_min_max
  from ..utils.fixes import astype
  from ..utils.fixes import in1d
  from ..utils import column_or_1d
  from ..utils.validation import check_array
  from ..utils.validation import check_is_fitted
  from ..utils.validation import _num_samples
  from ..utils.multiclass import unique_labels
  from ..utils.multiclass import type_of_target
  from ..externals import six
label_desc: Use image node_id 1 for calling a global function with example usage: _check_numpy_unicode_bug(labels) without return types