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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def reverse(args):
 """Returns a list of file database identifiers given the path stems"""


  from .query import Database
  db = Database()

  output = sys.stdout
  if args.selftest:
    from bob.db.utils import null
    output = null()

  r = db.reverse(args.path)
  for f in r: output.write('%d\n' % f.id)

  if not r: return 1

  return 0