def system_drop_column_family(self, column_family):
    """
    drops a column family. returns the new schema id.

    Parameters:
     - column_family
    """
    self._seqid += 1
    d = self._reqs[self._seqid] = defer.Deferred()
    self.send_system_drop_column_family(column_family)
    return d
def system_drop_column_family ( self , column_family ) : self . _seqid += 1 d = self . _reqs [ self . _seqid ] = defer . Deferred ( ) self . send_system_drop_column_family ( column_family ) return d
drops a column family. returns the new schema id.

    Parameters:
     - column_family