class_docstr: Class for recovering a mapping used by FeatureHasher.
code: def partial_fit(self, X, y=None):
      # type: (Iterable[str], Any) -> FeatureUnhasher
      self._term_counts.update(X)
      self._attributes_dirty = True
      return self
  
imports: from __future__ import absolute_import
  from collections import defaultdict, Counter
  from itertools import chain
  from typing import List, Iterable, Any, Dict, Tuple, Union
  import numpy
  import six
  from sklearn.base import BaseEstimator, TransformerMixin
  from sklearn.feature_extraction.text import HashingVectorizer, FeatureHasher
  from sklearn.pipeline import FeatureUnion
  from eli5._feature_names import FeatureNames
label_desc: Use image node_id 3 for calling the FeatureUnhasher obj's underlying member method code with example usage: obj.partial_fit(X, y) and returns: self