nboard/clean.py

#!/usr/bin/env python3

import json

with open("nboard.json", "r") as file:
    data = json.load(file)

print(len(data))

data = {k: v for k, v in data.items() if v is not " "}

print(len(data))

with open("nboard.json", "w") as file:
    json.dump(data, file)