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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 main(args):
 """ main entry point for the GenomicIntJaccard script. :param args: the arguments for this script, as a list of string. Should already have had things like the script name stripped. That is, if there are no args provided, this should be an empty list. """

  # get options and arguments
  ui = getUI(args)

  if ui.optionIsSet("test"):
    # just run unit tests
    unittest.main(argv=[sys.argv[0]])
  elif ui.optionIsSet("help"):
    # just show help
    ui.usage()
  else:
    verbose = ui.optionIsSet("verbose")
    stranded = ui.optionIsSet("stranded")

    if stranded:
      sys.stderr.write("Sorry, stranded mode hasn't been implemented yet.")
      sys.exit()

    # we required two input files, so we know these will be present...
    regions_1 = [e for e in BEDIterator(ui.getArgument(0), verbose=verbose)]
    regions_2 = [e for e in BEDIterator(ui.getArgument(1), verbose=verbose)]

    print jaccardIndex(regions_1, regions_2)