class_docstr: A constraint disallowing the modification of stopwords.
docstr: Returns the word indices in ``current_text`` which are able to be
  modified.
docstr_tok: ["Returns","the","word","indices","in","``","current_text","``","which","are","able","to","be","modified","."]
code: def _get_modifiable_indices(self, current_text):
      """Returns the word indices in ``current_text`` which are able to be
      modified."""
      non_stopword_indices = set()
      for i, word in enumerate(current_text.words):
          if word not in self.stopwords:
              non_stopword_indices.add(i)
      return non_stopword_indices
  
file_path: TextAttack/textattack/constraints/pre_transformation/stopword_modification.py
imports: import nltk
  from textattack.constraints import PreTransformationConstraint
  from textattack.shared.validators import transformation_consists_of_word_swaps
label_desc: Use image node_id 2 for calling the StopwordModification obj's underlying member method code with example usage: obj._get_modifiable_indices(current_text) and returns: non_stopword_indices