def _valid_customize(value):
    if not isinstance(value, dict):
        raise vol.Invalid('Expected dictionary')

    for key, val in value.items():
        if not valid_entity_id(key):
            raise vol.Invalid('Invalid entity ID: {}'.format(key))

        if not isinstance(val, dict):
            raise vol.Invalid('Value of {} is not a dictionary'.format(key))

    return value
Given an artist string, split the "main" artist from any artist
dataset/ETHPy150Open home-assistant/home-assistant/homeassistant/config.py/_valid_customize--crossover with--dataset/ETHPy150Open beetbox/beets/beetsplug/ftintitle.py/split_on_feat