config.py

import json

config_dict = {}
visited_keys = []
def get_config_item_or_set_default(key, default_value, validator, disable_empty_as_none=False):
    global config_dict, visited_keys

    if key not in visited_keys:
        visited_keys.append(key)

    if key not in config_dict:
        config_dict[key] = default_value
        return default_value

    v = config_dict.get(key, None)
    if not disable_empty_as_none:
        if v is None or v == '':
            v = 'None'
    if validator(v):
        return v
    else:
        if v is not None:
            print(
                f'Failed to load config key: {json.dumps({key: v})} is invalid; will use {json.dumps({key: default_value})} instead.')
        config_dict[key] = default_value
        return default_value


available_aspect_ratios = get_config_item_or_set_default(
    key='available_aspect_ratios',
    default_value=[
        '704*1408', '704*1344', '768*1344', '768*1280', '832*1216', '832*1152',
        '896*1152', '896*1088', '960*1088', '960*1024', '1024*1024', '1024*960',
        '1088*960', '1088*896', '1152*896', '1152*832', '1216*832', '1280*768',
        '1344*768', '1344*704', '1408*704', '1472*704', '1536*640', '1600*640',
        '1664*576', '1728*576'
    ],
    validator=lambda x: isinstance(x, list) and all('*' in v for v in x) and len(x) > 1
)
default_aspect_ratio = get_config_item_or_set_default(
    key='default_aspect_ratio',
    default_value='1152*896' if '1152*896' in available_aspect_ratios else available_aspect_ratios[0],
    validator=lambda x: x in available_aspect_ratios
)