code: def fit_transform(self, y):
      raise NotImplementedError
  
file_path: ivy/ivy/functional/frontends/sklearn/preprocessing/_label.py
imports: from ivy.functional.frontends.sklearn.base import BaseEstimator, TransformerMixin
  import ivy
label_desc: Use image node_id 2 for calling the LabelEncoder obj's underlying member method code with example usage: obj.fit_transform(y) without return types