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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 register_blueprint(self, blueprint: Blueprint, url_prefix: Optional[str]=None) -> None: """Register a blueprint on the app. This results in the blueprint's routes, error handlers Arguments: blueprint: The blueprint to register. url_prefix: Optional prefix to apply to all paths. """

        first_registration = False
        if blueprint.name in self.blueprints and self.blueprints[blueprint.name] is not blueprint:
            raise RuntimeError(
                f"Blueprint name '{blueprint.name}' "
                f"is already registered by {self.blueprints[blueprint.name]}. "
                "Blueprints must have unique names",
            )
        else:
            self.blueprints[blueprint.name] = blueprint
            first_registration = True
        blueprint.register(self, first_registration, url_prefix=url_prefix)