chapter_number = None
index = lesson.get('index')
element_index = lesson.get('elementIndex')
- if (isinstance(index, int) and isinstance(element_index, int) and
- index < element_index):
+ if (isinstance(index, int) and isinstance(element_index, int)
+ and index < element_index):
chapter_number = element_index - index
chapter = (chapters[chapter_number - 1]
if chapter_number - 1 < len(chapters) else None)