class_docstr: Label Encoder that groups infrequent values into one label.
  
  Code from https://github.com/jeongyoonlee/Kaggler/blob/master/kaggler/preprocessing/data.py
  
  Attributes:
      min_obs (int): minimum number of observation to assign a label.
      label_encoders (list of dict): label encoders for columns
      label_maxes (list of int): maximum of labels for columns
code: def __repr__(self):
      return ("LabelEncoder(min_obs={})").format(self.min_obs)
  
imports: import logging
  import numpy
  import pandas
  from scipy import sparse
  from sklearn import base
label_desc: Use image node_id 2 for calling the LabelEncoder obj's underlying member method code with example usage: obj.__repr__() and returns: str