new_contents: from Bio import SeqIO
  
  genome = list(SeqIO.parse("/home/maxwell.a.sherman/genomes/fugu.fa", "fasta"))
  sizes = []
  
  for scaffold in genome:
      sizes.append(len(scaffold))
  
  sizes.sort(reverse = True)
  target = float(sum(sizes)) * 0.9
  total = 0 # running total
  score = -1 # keeps track of which size
  
  while total < target:
      score += 1
      total += sizes[score]
  
  print sizes[score]
  
subject: Add N90 scoring program