code: function getSerializer(target, property /* | keyof T*/) {
      // get the class constructor
      const constr = target.constructor;
      // retrieve the current metadata
      const metadata = Reflect.getMetadata(METADATA_serializeWith, constr) || {};
      if (metadata.hasOwnProperty(property))
          return metadata[property];
      // If there's no custom serializer, try to find a default one
      const type = getPropertyType(target, property);
      if (type && type.name in defaultSerializers) {
          return defaultSerializers[type.name];
      }
  }
docs: Retrieves the serializer for a given property