def _validate_config_file(config_file):
    if not os.path.exists(config_file):
        raise ConfigurationError("Specified configuration file not"
                                 " found: {0}".format(config_file))
    if not os.path.isfile(config_file):
        raise ConfigurationError("Specified configuration file is not"
                                 " a file: {0}".format(config_file))
Ensure that config_file exists and is a file.
dataset/ETHPy150Open Yelp/pyleus/pyleus/configuration.py/_validate_config_file