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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 add_janitor(self, janitor):
 """Add janitor to the room"""


        if not self.owner and not self.admin:
            raise RuntimeError("Not enough street creed to do this")

        janitor = janitor.strip().lower()
        if not janitor:
            raise ValueError("Empty strings cannot be janitors")

        if janitor in self.config.janitors:
            return

        self.config.janitors.append(janitor)
        self.__set_config_value("janitors", self.config.janitors)