diff --git a/src/TgBotLib/Objects/PhotoSize.php b/src/TgBotLib/Objects/PhotoSize.php
index d75f996..0b8699d 100644
--- a/src/TgBotLib/Objects/PhotoSize.php
+++ b/src/TgBotLib/Objects/PhotoSize.php
@@ -7,30 +7,11 @@
 
     class PhotoSize implements ObjectTypeInterface
     {
-        /**
-         * @var string
-         */
-        private $file_id;
-
-        /**
-         * @var string
-         */
-        private $file_unique_id;
-
-        /**
-         * @var string
-         */
-        private $width;
-
-        /**
-         * @var string
-         */
-        private $height;
-
-        /**
-         * @var int|null
-         */
-        private $file_size;
+        private string $file_id;
+        private string $file_unique_id;
+        private string $width;
+        private string $height;
+        private ?int $file_size;
 
         /**
          * Identifier for this file, which can be used to download or reuse the file
@@ -85,9 +66,7 @@
         }
 
         /**
-         * Returns an array representation of the object
-         *
-         * @return array
+         * @inheritDoc
          */
         public function toArray(): array
         {
@@ -101,16 +80,16 @@
         }
 
         /**
-         * Constructs an object from an array representation
-         *
-         * @param array $data
-         * @return PhotoSize
-         * @noinspection DuplicatedCode
+         * @inheritDoc
          */
-        public static function fromArray(array $data): self
+        public static function fromArray(?array $data): ?PhotoSize
         {
-            $object = new self();
+            if($data === null)
+            {
+                return null;
+            }
 
+            $object = new self();
             $object->file_id = $data['file_id'] ?? null;
             $object->file_unique_id = $data['file_unique_id'] ?? null;
             $object->width = $data['width'] ?? null;