code: def dedupFasta(reads):
      
      seen = set()
      add = seen.add
      for read in reads:
          hash_ = md5(read.sequence.encode('UTF-8')).digest()
          if hash_ not in seen:
              add(hash_)
              yield read
docs: Remove sequence duplicates (based on sequence) from FASTA.
  
      @param reads: a C{dark.reads.Reads} instance.
      @return: a generator of C{dark.reads.Read} instances with no duplicates.