Ever wanted to reset the execution counts of the cells of a jupyter notebook to make it more presentable (or to hide experiments and tweaks from your teachers or colleagues) but re-running everything was not an option (too long, too risky, the numbers happened to be toooooo good)? Well, now you have a way!

reset_ipynb_exec_cnt.py

import argparse
import json

parser = argparse.ArgumentParser(
    description='Reset the execution count of the code cells of a jupyter notebook'
)

parser.add_argument('notebook', help='the input jupyter notebook')
parser.add_argument('-i', '--inplace',
                    help='change the notebook file inplace', action='store_true')
parser.add_argument('-o', '--output',
                    help='if not inplace, the name of the output notebook')

args = parser.parse_args()

with open(args.notebook, 'r') as f:
    notebook_json = json.load(f)

exec_cnt = 1
for cell in filter(lambda c : c['cell_type'] == 'code', notebook_json['cells']):
    cell['execution_count'] = exec_cnt
    if 'outputs' in cell:
        for o in cell['outputs']:
            if 'execution_count' in o:
                o['execution_count'] = exec_cnt
    exec_cnt += 1

if args.inplace:
    print('WARNING: You are about to overwrite the `%s` jupyter notebook file!' % args.notebook)
    if input('Are you sure you want to continue? [y/N] ') != 'y':
        print('Aborted.')
        exit(0)
    outfile = args.notebook
else:
    if args.output is not None:
        outfile = args.output
    else:
        outfile = args.notebook.split('.ipynb')[0] + '_reset.ipynb'

with open(outfile, 'w') as f:
    json.dump(notebook_json, f)