Create `metadata.json` for existing Minecraft data

create_metadata.py

# note: specifically for the minecraft data, based on "minecraft_video_dataset.py"
import json                                                                                                                                          [1/110]
from pathlib import Path                                                                                                                                    

splits = ["training", "validation"]
metadata = {}
for split in splits:
    data_dir = Path("data/minecraft") / split
    paths = sorted(list(data_dir.glob("**/*.npz")), key=lambda x: x.name)
    lengths = [300] * len(paths)
    metadata[split] = lengths
json.dump(metadata, open("data/minecraft/metadata.json", "w"))