code: def category_file_strings(corpus):
      for cat in corpus.categories():
          for fileid in corpus.fileids(categories=[cat]):
              yield cat, corpus.raw(fileids=[fileid])
  
file_path: nltk-trainer/nltk_trainer/classification/corpus.py
imports: import itertools
label_desc: Use image node_id 12 for calling a global function with example usage: category_file_strings(corpus) without return types