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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 hstack(tup):
 """ Horizontally stack a sequence of value bounds pairs. Parameters tup: sequence a sequence of value, ``Bound`` pairs Returns ------- value: ndarray a horizontally concatenated array1d bounds: a list of Bounds """

    vals, bounds = zip(*tup)
    stackvalue = np.hstack(vals)
    stackbounds = list(chain(*bounds))

    return stackvalue, stackbounds