def METHOD_NAME(func):
    """Check input config values for check_connection and stream functions. It will raise an exception if there is an parsing error"""
    @wraps(func)
    def decorator(self_, *args, **kwargs):
        for arg in args:
            if isinstance(arg, Mapping):
                try:
                    # parse date strings by the pendulum library. It will raise the exception ParserError if it is some format mistakes.
                    pendulum.parse(arg["start_date"])
                    # try to check an end_date value. It can be ussed for different CI tests
                    end_date = arg.get("end_date")
                    if end_date:
                        pendulum.parse(end_date)
                except ParserError as e:
                    raise Exception(f"{str(e)}. Example: 2021-01-01T00:00:00Z")
                break
        return func(self_, *args, **kwargs)
    return decorator