code: public FirewallPolicyFilter where(Predicate<FirewallPolicyMetadata> predicate) {
          checkNotNull(predicate, "Predicate must be not a null");
  
          this.predicate = this.predicate.and(predicate);
  
          return this;
      }
docs: Method allow to specify custom template filtering predicate
  
  @param predicate is not null filtering expression
  @return {@link FirewallPolicyFilter}