new_contents: import argparse
  
  import numpy as np
  
  parser = argparse.ArgumentParser(description='merge cross sections')
  parser.add_argument('outfile', help='name of output merged file')
  parser.add_argument('infiles', nargs='+', help='files to merge')
  args = parser.parse_args()
  
  
  res = {}
  for f in args.infiles:
      info = np.load(f.replace('file:', ''))[()]
      for process, cross_sections in info.items():
          try:
              res[process] = np.vstack([res[process], cross_sections])
          except KeyError:
              res[process] = cross_sections
  
  np.save(args.outfile, res)
  
subject: Add merge script