Proposed changes to jupytext-markdown

Notebook with metadata and long cells.md

jupyter
kernelspec display_name language name Python 3 python python3

Part one - various cells

Here we have a markdown cell

with two blank lines

Now we have a markdown cell with a code block inside it

1 + 1

After that cell we'll have a code cell

2 + 2


3 + 3

Followed by a raw cell

This is 
the content
of the raw cell

Part two - cell metadata

This is a markdown cell with cell metadata {"key": "value"}

"""This is a code cell with metadata `{"tags":["parameters"], ".class":null}`"""

This is a raw cell with cell metadata `{"key": "value"}`