Shuffles indices X, y, and sample_weight together

def shuffle_data(X, y=None, sample_weight=None):
    ''' Shuffles indices X, y, and sample_weight together'''
    if len(X) > 1:
        ind = np.arange(len(X), dtype=np.int)
        np.random.shuffle(ind)
        Xt = X[ind]
        yt = y
        swt = sample_weight

        if yt is not None:
            yt = yt[ind]
        if swt is not None:
            swt = swt[ind]

        return Xt, yt, swt
    else:
        return X, y, sample_weight