code: def parse_hpxregion(region):
      
  
      m = re.match(r'([A-Za-z\_]*?)\((.*?)\)', region)
      if m is None:
          raise Exception('Failed to parse hpx region string.')
  
      if not m.group(1):
          return re.split(',', m.group(2))
      else:
          return [m.group(1)] + re.split(',', m.group(2))
docs: Parse the HPX_REG header keyword into a list of tokens.