class_docstr: Class that holds information about a block of formatted lines.
  
  This is introduced so that the EmptyLineTracker can look behind the standalone
  comments and adjust their empty lines for class or def lines.
class_docstr_tok: ["Class","that","holds","information","about","a","block","of","formatted","lines",".","This","is","introduced","so","that","the","EmptyLineTracker","can","look","behind","the","standalone","comments","and","adjust","their","empty","lines","for","class","or","def","lines","."]
code: def all_lines(self) -> List[str]:
      empty_line = str(Line(mode=self.mode))
      prefix = make_simple_prefix(
          self.before, self.form_feed, empty_line
      )
      return [prefix] + self.content_lines + [empty_line * self.after]
  
imports: import itertools
  import math
  from dataclasses import dataclass, field
  from typing import Callable, Dict, Iterator, List, Optional, Sequence, Tuple, TypeVar, Union, cast
  from black.brackets import COMMA_PRIORITY, DOT_PRIORITY, BracketTracker
  from black.mode import Mode, Preview
  from black.nodes import BRACKETS, CLOSING_BRACKETS, OPENING_BRACKETS, STANDALONE_COMMENT, TEST_DESCENDANTS, child_towards, is_docstring, is_import, is_multiline_string, is_one_sequence_between, is_type_comment, is_type_ignore_comment, is_with_or_async_with_stmt, make_simple_prefix, replace_child, syms, whitespace
  from black.strings import str_width
  from blib2to3.pgen2 import token
  from blib2to3.pytree import Leaf, Node
label_desc: Use image node_id 1 for calling the LinesBlock obj's underlying member method code with example usage: obj.all_lines() and returns: unknown