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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(self, route_name, **args):
        ''' Builds an URL out of a named route and some parameters.'''
        try:
            return self.named[route_name] % args
        except KeyError:
            raise RouteBuildError("No route found with name '%s'." % route_name)