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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 _std_tuple_of(var=None, std=None, interval=None):
 """ Convienence function for plotting. Given one of var, standard deviation, or interval, return the std. Any of the three can be an iterable list. Examples -------- (1, 2, 3) """


    if std is not None:
        if np.isscalar(std):
            std = (std,)
        return std


    if interval is not None:
        if np.isscalar(interval):
            interval = (interval,)

        return norm.interval(interval)[1]

    if var is None:
        raise ValueError("no inputs were provided")

    if np.isscalar(var):
        var = (var,)
    return np.sqrt(var)