Convert .py with cells (e.g., from Hydrogen) to .ipynb

convert_to_ipynb.py

from nbformat import v3, v4
import sys
import os
infilename=sys.argv[1]
outfilename=os.path.splitext(infilename)[0]+".ipynb"
with open(infilename) as fpin:
    text = fpin.read()

text=text.replace("#%%", "# <codecell>")
text=text.replace("# %%", "# <codecell>")
text=text.replace("#<codecell>", "# <codecell>")

import re
text=re.sub(r'(# <codecell>)(.*)(\n)', r'# <markdowncell>\n# #### \2\n# <codecell>\n', text)

nbook = v3.reads_py(text)
nbook = v4.upgrade(nbook)
jsonform = v4.writes(nbook) + "\n"
with open(outfilename, "w") as fpout:
    fpout.write(jsonform)

Supports only #%% and <codecell> as cell delimiters and adds comments on cell delimiter line as markdown.

@ttor This is neat !