def zscore(dat, mean, sigma):
    """Calculates zscore of a data point in (or outside of) a dataset
    zscore: how many sigmas away is a value from the mean of a dataset?

    Parameters
    ----------
    dat: float
        Data point
    mean: float
        Mean of dataset
    sigma: flaot
        Sigma of dataset

    """
    zsc = (dat-mean)/sigma
    return zsc