def seqids_from_otu_to_seqid(otu_to_seqid):
 return set(flatten(otu_to_seqid.values()))

def seqids_from_otu_to_seqid ( otu_to_seqid ) : return set ( flatten ( otu_to_seqid . values ( ) ) )
returns set of all seq ids from libs .