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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 prepare_topoplots(topo, values):
 """Prepare multiple topo maps for cached plotting. .. note:: Parameter `topo` is modified by the function by calling :func:`~eegtopo.topoplot.Topoplot.set_values`. Parameters topo : :class:`~eegtopo.topoplot.Topoplot` Scalp maps are created with this class values : array, shape = [n_topos, n_channels] Channel values for each topo plot Returns ------- topomaps : list of array The map for each topo plot """

    values = np.atleast_2d(values)

    topomaps = []

    for i in range(values.shape[0]):
        topo.set_values(values[i, :])
        topo.create_map()
        topomaps.append(topo.get_map())

    return topomaps