docs: def enumarg(enum, arg):
      """Return enum member from its name or value.
  
      >>> enumarg(TIFF.PHOTOMETRIC, 2)
      <PHOTOMETRIC.RGB: 2>
      >>> enumarg(TIFF.PHOTOMETRIC, 'RGB')
      <PHOTOMETRIC.RGB: 2>
  
      """
      try:
          return enum(arg)
      except Exception:
          try:
              return enum[arg.upper()]
          except Exception:
              raise ValueError('invalid argument %s' % arg)