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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 create_geoms(self, plot):
 """ This guide is not geom based Return self if colorbar will be drawn and None if not. """

        for l in plot.layers:
            exclude = set()
            if isinstance(l.show_legend, dict):
                l.show_legend = rename_aesthetics(l.show_legend)
                exclude = {ae for ae, val in l.show_legend.items()
                           if not val}
            elif l.show_legend not in (None, True):
                continue

            matched = self.legend_aesthetics(l, plot)

            # layer uses guide
            if set(matched) - exclude:
                break
        # no break, no layer uses this guide
        else:
            return None

        return self