shortcuts for editing code indentation in jupyter notebook

You can select the code block using Ctrl + A and then use

Ctrl + ] indent
Ctrl + [ dedent

For complete list of Jupyter notebook key shortcuts visit here

Ctrl-] : indent
Ctrl-[ : shifting back indentation

if it doesn't work, then try:

Tab : indent
Shift + Tab : shfting back indentation

just select and drag from the beginning of the code piece until the line you wish for while holding alt to choose multiple indexes at multiple lines (or you can use it for rectangular selection too)

after that tab for right indentation and shift+tab for left indentation