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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 tables_(self) -> list: """Return a list of the existing tables in a database :return: list of the table names :rtype: list :example: ``tables = ds.tables_()`` """

        if self._check_db() == False:
            return
        try:
            return self._tables()
        except Exception as e:
            self.err(e, "Can not print tables")