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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 slice_columns(x, using=None):
 """ Slice a numpy array to make columns Parameters x : ndarray A numpy array instance using : list of integer or slice instance or None, optional A list of index or slice instance Returns ------- ndarray A list of numpy array columns sliced """

    if using is None:
        using = range(0, len(x[0]))
    return [x[:,s] for s in using]