class_docstr: Process unit to remove stop words.
  
  Example:
      >>> unit = StopRemoval()
      >>> unit.transform(['a', 'the', 'test'])
      ['test']
      >>> type(unit.stopwords)
      <class 'list'>
docstr: Get stopwords based on language.
  
  :params lang: language code.
  :return: list of stop words.
docstr_tok: ["Get","stopwords","based","on","language",".",":","params","lang",":","language","code",".",":","return",":","list","of","stop","words","."]
code: def stopwords(self) -> list:
      """
      Get stopwords based on language.
  
      :params lang: language code.
      :return: list of stop words.
      """
      return self._stop
  
imports: import nltk
  from .unit import Unit
label_desc: Use image node_id 3 for calling the StopRemoval obj's underlying member method code with example usage: obj.stopwords() and returns: self