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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 exist(self, table: str, libref: str = "") -> bool: """ Does the SAS data set currently exist :param table: the name of the SAS Data Set :param libref: the libref for the Data Set, defaults to WORK, or USER if assigned :return: Boolean True it the Data Set exists and False if it does not :rtype: bool """

        return self._io.exist(table, libref)