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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def create_app(config='udata.settings.Defaults', override=None,
               init_logging=init_logging):
    '''Factory for a minimal application'''
    app = UDataApp(APP_NAME)
    app.config.from_object(config)

    settings = os.environ.get('UDATA_SETTINGS', join(os.getcwd(), 'udata.cfg'))
    if exists(settings):
        app.settings_file = settings  # Keep track of loaded settings for diagnostic
        app.config.from_pyfile(settings)

    if override:
        app.config.from_object(override)

    # Loads defaults from plugins
    for pkg in entrypoints.get_roots(app):
        if pkg == 'udata':
            continue  # Defaults are already loaded
        module = '{}.settings'.format(pkg)
        if pkgutil.find_loader(module):
            settings = pkgutil.get_loader(module)
            for key, default in settings.__dict__.items():
                app.config.setdefault(key, default)

    app.json_encoder = UDataJsonEncoder

    app.debug = app.config['DEBUG'] and not app.config['TESTING']

    app.wsgi_app = ProxyFix(app.wsgi_app)

    init_logging(app)
    register_extensions(app)

    return app