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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 connect(self, url: str):
 """Connect to the database and set it as main database :param url: path to the database, uses the Sqlalchemy format :type url: str :example: ``ds.connect("sqlite:///mydb.slqite")`` """

        try:
            self.db = dataset.connect(url, row_type=stuf)
        except Exception as e:
            self.err(e, "Can not connect to database")
            return
        if self.db is None:
            self.err("Database " + url + " not found")
            return
        self.ok("Db", self.db.url, "connected")