def as_session(name_or_func):  # decorator
    """print start/title/end info before and after the function call

    Args:
        title: title will show after the start, if has any
    """
    if callable(name_or_func):  # no name provided
        func = name_or_func
        name = func.__name__
        name = "".join([(' ' + x) if x.isupper() else x for x in name])
        name = name.replace('_', ' ')
        return as_session(name)(func)  # deco(func) -> deco(name)(func)
    else:
        name = name_or_func

    def get_func(func):
        @wraps(func)
        def wrapper(*args, **kwargs):
            start()
            title(name)
            result = func(*args, **kwargs)
            end()
            return result
        return wrapper
    return get_func