"Traditional parsing"

def parse(input):
  accessions = []
  ...
  for line in input:
    ...
    if line.startswith("AC  "):
      # AC   P97430; O09081; O09082;
      words = line.replace(";", " ").split()
      accessions.extend(words[1:])
    ...
  return SeqRecord(...
                   accessions = accessions,
                   ...)

 
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