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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 assign_routes(self, app):
 """Register routes with the app."""

        for grp in self.filters:
            for f in self.filters[grp]:
                if f.route_func:
                    f.register_route(app)

        for c in self.charts:
            if c.route_func:
                c.register_route(app)