def _slice(self, level):
if level >= len(self.taxonomy):<EOL><INDENT>raise IndexError('<STR_LIT>')<EOL><DEDENT>res = []<EOL>for ident in sorted(list(self.keys())):<EOL><INDENT>res.append((self[ident]['<STR_LIT>'], self[ident]['<STR_LIT>'][level]))<EOL><DEDENT>return res<EOL>
Return list of tuples of ident and lineage ident for given level
(numbered rank)