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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_one(self, url: str,
                url_properties: Optional[URLProperties]=None,
                url_data: Optional[URLData]=None):
        '''Add a single URL to the table.

        Args:
            url: The URL to be added
            url_properties: Additional values to be saved
            url_data: Additional data to be saved
        '''
        self.add_many([AddURLInfo(url, url_properties, url_data)])