code: func IsMobileNumberPortableRegion(regionCode string) bool {
  	metadata := getMetadataForRegion(regionCode)
  	if metadata == nil {
  		return false
  	}
  	return metadata.GetMobileNumberPortableRegion()
  }
docs: // Returns true if the supplied region supports mobile number portability.
  // Returns false for invalid, unknown or regions that don't support mobile
  // number portability.