code: def test_empty_document():
      document = build_document()
      summarizer = _build_summarizer(EMPTY_STOP_WORDS)
  
      returned = summarizer(document, 10)
      assert len(returned) == 0
  
file_path: sumy/tests/test_summarizers/test_sum_basic.py
imports: from __future__ import absolute_import, division, print_function, unicode_literals
  import pytest
  from sumy.models.dom._sentence import Sentence
  from sumy.nlp.tokenizers import Tokenizer
  from sumy.summarizers.sum_basic import SumBasicSummarizer
  from sumy.nlp.stemmers import Stemmer
  from ..utils import build_document
label_desc: Use image node_id 2 for calling a global function with example usage: test_empty_document() without return types