class_docstr: Parses simple plain text in following format:
  
  HEADING
  This is text of 1st paragraph. Some another sentence.
  
  This is next paragraph.
  
  HEADING IS LINE ALL IN UPPER CASE
  This is 3rd paragraph with heading. Sentence in 3rd paragraph.
  Another sentence in 3rd paragraph.
  
  Paragraphs are separated by empty lines. And that's all :)
class_docstr_tok: ["Parses","simple","plain","text","in","following","format",":","HEADING","This","is","text","of","1st","paragraph",".","Some","another","sentence",".","This","is","next","paragraph",".","HEADING","IS","LINE","ALL","IN","UPPER","CASE","This","is","3rd","paragraph","with","heading",".","Sentence","in","3rd","paragraph",".","Another","sentence","in","3rd","paragraph",".","Paragraphs","are","separated","by","empty","lines",".","And","that","'s","all",":",")"]
code: def _to_sentences(self, lines):
      text = ""
      sentence_objects = []
  
      for line in lines:
          if isinstance(line, Sentence):
              if text:
                  sentence_objects.extend(
                      self._to_sentence_objects(text)
                  )
  
              sentence_objects.append(line)
              text = ""
          else:
              text += " " + line
  
      text = text.strip()
      if text:
          sentence_objects.extend(self._to_sentence_objects(text))
  
      return sentence_objects
  
file_path: sumy/sumy/parsers/plaintext.py
imports: from __future__ import absolute_import
  from __future__ import division, print_function, unicode_literals
  from io import open
  from .parser import DocumentParser
  from .._compat import to_unicode
  from ..models.dom import ObjectDocumentModel, Paragraph, Sentence
  from ..utils import cached_property
label_desc: Use image node_id 7 for calling the PlaintextParser obj's underlying member method code with example usage: obj._to_sentences(lines) and returns: sentence_objects