Convert a Jupyter notebook to html output in native Python

Question

I know I can call

jupyter nbconvert --execute --to html notebook.ipynb

from shell, or do a system call from Python:

import os
os.system('jupyter nbconvert --execute --to html notebook.ipynb')

But having to do this with a system call when an nbconvert module is available in native Python seems very odd!

I want to write native python to execute and convert a iPython notebook to an html file. I studied the official documentation a little but couldn't piece things together. My questions are:

1. Is there an example to convert notebooks to html in native Python?
2. Is there a compelling reason not to do it?

Answer 1

OK I figured out after some trial and error:

import nbformat
from nbconvert.preprocessors import ExecutePreprocessor
from nbconvert import HTMLExporter

# read source notebook
with open('report.ipynb') as f:
    nb = nbformat.read(f, as_version=4)

# execute notebook
ep = ExecutePreprocessor(timeout=-1, kernel_name='python3')
ep.preprocess(nb)

# export to html
html_exporter = HTMLExporter()
html_exporter.exclude_input = True
html_data, resources = html_exporter.from_notebook_node(nb)

# write to output file
with open("notebook.html", "w") as f:
    f.write(html_data)

Admittedly a lot more work than a single os.system call, but I'm surprised there are so little native python examples out there...