code: def parse_region(s: str) -> Region:
      """Attempts to parse the string into a valid region; raises a sensible argparse
      error if that's not possible.
  
      """
      try:
          return u.any_of(s, Region)
      except ValueError:
          valid_values = u.enum_vals(valid_regions())
          raise argparse.ArgumentTypeError(
              "'{}' isn't a valid region. \
  Must be one of {}.".format(
                  s, valid_values
              )
          )
  
imports: import argparse
  from enum import Enum
  from typing import Callable, List, NamedTuple, Optional, Set, Union
  import caliban.util
label_desc: Use image node_id 8 for calling a global function with example usage: parse_region(s) and returns: u