def METHOD_NAME(source, destination):
    """
    Recursively merges two dictionaries.
    Args:
        source (`dict`): The dictionary to merge into `destination`.
        destination (`dict`): The dictionary to merge `source` into.
    """
    for key, value in source.items():
        if isinstance(value, dict):
            node = destination.setdefault(key, {})
            METHOD_NAME(value, node)
        else:
            destination[key] = value
    return destination