* @param string $title The group name
         */
        public function __construct(string $title) {
-               $this->title = (string) $title;
+               $this->title = $title;
                $this->users = new ArrayCollection();
        }
 
         *
         * @param string $title The group name
         *
-        * @return User
+        * @return Group
         */
-       public function setTitle(string $title) {
+       public function setTitle(string $title): Group {
                $this->title = $title;
 
                return $this;
         *
         * @param \DateTime $created
         *
-        * @return User
+        * @return Group
         */
-       public function setCreated(\DateTime $created) {
+       public function setCreated(\DateTime $created): Group {
                $this->created = $created;
 
                return $this;
         *
         * @param \DateTime $updated
         *
-        * @return User
+        * @return Group
         */
-       public function setUpdated(\DateTime $updated) {
+       public function setUpdated(\DateTime $updated): Group {
                $this->updated = $updated;
 
                return $this;