import logging


def get_logger(logger_name):
    """
        Get the dev or prod logger (avoids having to import 'logging' in calling code).

        Parameters:
            logger_name - 'dev' or 'prod'

        Returns:
            Logger to use for logging statements.
    """
    valid_logger_names = ['dev','prod']

    if logger_name in valid_logger_names:
        return logging.getLogger(logger_name)
    else:
        raise ValueError("Invalid logger name: allowed values are "+",".join(valid_logger_names))
        return None