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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 plot_weights(self, index=None, plot_type="motif_raw", figsize=None, ncol=1, **kwargs):
 """Plot filters as heatmap or motifs index = can be a particular index or a list of indicies **kwargs - additional arguments to concise.utils.plot.heatmap """


        if "heatmap" in self.AVAILABLE_PLOTS and plot_type == "heatmap":
            return self._plot_weights_heatmap(index=index, figsize=figsize, ncol=ncol, **kwargs)
        elif plot_type[:5] == "motif":
            return self._plot_weights_motif(index=index, plot_type=plot_type, figsize=figsize, ncol=ncol, **kwargs)
        else:
            raise ValueError("plot_type needs to be from {0}".format(self.AVAILABLE_PLOTS))