Add shorthands for timezone to tz

app/Models/Airport.php

@@ -88,10 +88,20 @@ class Airport extends BaseModel
     }
 
     /**
+     * Shorthand for getting the timezone
      * @return string
      */
     public function getTzAttribute(): string
     {
         return $this->timezone;
     }
+
+    /**
+     * Shorthand for setting the timezone
+     * @param $value
+     */
+    public function setTzAttribute($value)
+    {
+        $this->attributes['timezone'] = $value;
+    }
 }

app/Models/User.php

@@ -93,14 +93,23 @@ class User extends Authenticatable
     }
 
     /**
-     * Return the timezone
+     * Shorthand for getting the timezone
-     * @return mixed
+     * @return string
      */
-    public function getTzAttribute()
+    public function getTzAttribute(): string
     {
         return $this->timezone;
     }
 
+    /**
+     * Shorthand for setting the timezone
+     * @param $value
+     */
+    public function setTzAttribute($value)
+    {
+        $this->attributes['timezone'] = $value;
+    }
+
     /**
      * @param mixed $size Size of the gravatar, in pixels
      * @return string