code: public function setIdentityUuid(?string $identityUuid)
      {
          if (null !== $identityUuid) {
              if (!preg_match('/^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/i', $identityUuid)) {
                  throw new InvalidArgumentException('Identity uuid is not valid.');
              }
          }
  
          $this->identityUuid = $identityUuid;
  
          return $this;
      }
docs: Set identity uuid
  
  @param string $identityUuid
  @return object
  @throws \InvalidArgumentException