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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 tableNames(self, dbName=None):
 """Returns a list of names of tables in the database ``dbName``. :param dbName: string, name of the database to use. Default to the current database. :return: list of table names, in string True True """

        if dbName is None:
            return [name for name in self._ssql_ctx.tableNames()]
        else:
            return [name for name in self._ssql_ctx.tableNames(dbName)]