class_docstr: Process unit for token stemming.
  
  :param stemmer: stemmer to use, `porter` or `lancaster`.
class_docstr_tok: ["Process","unit","for","token","stemming",".",":","param","stemmer",":","stemmer","to","use",",","`","porter","`","or","`","lancaster","`","."]
docstr: Initialization.
docstr_tok: ["Initialization","."]
code: def __init__(self, stemmer="porter"):
      """Initialization."""
      self.stemmer = stemmer
  
imports: import nltk
  from .unit import Unit
label_desc: Use image node_id 1 to create a new Stemming object from inherited base classes: Unit with example: obj = Stemming(stemmer)