AtomicFile

Writeable file object that atomically updates a file.

All writes will go to a temporary file. Call close() explicitly when you are done writing, and AtomicFile will rename the temporary copy to the original name, making the changes visible. If the object is destroyed without being closed, all your writes are discarded.

AtomicFile is friendly to with statement.

from atomicfile import AtomicFile

with AtomicFile("panic.txt", "w") as f:
    f.write(json.dumps(big_data_array_100MB, sort_keys=True, indent=4))

pip install atomicfile