How to Load, Save, and Split JSON Data in Python

import json
from pathlib import Path


def load_json_data(file_path):
    """Load JSON data from a file, returning an empty dict if missing."""
    path = Path(file_path)
    if path.exists():
        with path.open("r", encoding="utf-8") as f:
            return json.load(f)
    return {}


def save_json_data(data, file_path):
    """Save data to a JSON file with pretty formatting."""
    path = Path(file_path)
    with path.open("w", encoding="utf-8") as f:
        json.dump(data, f, indent=2)


def split_data(data, train_ratio=0.8):
    """Split dictionary data into train and test subsets by ratio."""
    items = list(data.items())
    split_index = int(len(items) * train_ratio)
    train_items = items[:split_index]
    test_items = items[split_index:]
    return dict(train_items), dict(test_items)


if __name__ == "__main__":
    sample = {"user1": 25, "user2": 30, "user3": 22, "user4": 35, "user5": 28}
    save_json_data(sample, "temp_data.json")

    loaded = load_json_data("temp_data.json")
    train, test = split_data(loaded, train_ratio=0.6)

    print("Loaded data:", loaded)
    print("Train set:", train)
    print("Test set:", test)

    # Cleanup temp file
    Path("temp_data.json").unlink()