code: def _get_positions_to_highlight(self, document):
          
          # Try for the character under the cursor.
          if document.current_char and document.current_char in self.chars:
              pos = document.find_matching_bracket_position(
                      start_pos=document.cursor_position - self.max_cursor_distance,
                      end_pos=document.cursor_position + self.max_cursor_distance)
  
          # Try for the character before the cursor.
          elif (document.char_before_cursor and document.char_before_cursor in
                self._closing_braces and document.char_before_cursor in self.chars):
              document = Document(document.text, document.cursor_position - 1)
  
              pos = document.find_matching_bracket_position(
                      start_pos=document.cursor_position - self.max_cursor_distance,
                      end_pos=document.cursor_position + self.max_cursor_distance)
          else:
              pos = None
  
          # Return a list of (row, col) tuples that need to be highlighted.
          if pos:
              pos += document.cursor_position  # pos is relative.
              row, col = document.translate_index_to_position(pos)
              return [(row, col), (document.cursor_position_row, document.cursor_position_col)]
          else:
              return []
docs: Return a list of (row, col) tuples that need to be highlighted.