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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 build_props(self):
 """Build the props dictionary."""

        props = {}
        if self.filters:
            props["filters"] = {}
            for grp in self.filters:
                props["filters"][grp] = [f.params for f in self.filters[grp]]
        if self.charts:
            props["charts"] = [c.params for c in self.charts]

        props["type"] = self.layout
        return props