I am working on developing my own python-like language support in CodeMirror and have generated parser files. Now I want to add indentation props to nodes which is where I am really confused and have been stuck quite a lot. I want a simple indentation strategy so that as soon as I press enter after : (colon), the newline has one unit extra indentation and then all other lines following should have same indentation (until I explicitly press backspace and alter the indentation in which case lines following that should follow same indentation).