Update vasr.py

vasr.py

@@ -116,7 +116,7 @@ class Vasr(datasets.GeneratorBasedBuilder):
             r_dict["B'_str"] = r_dict['D_img']
             for img in ['A_img', 'B_img', 'C_img', 'D_img']:
                 if r_dict[img] == self.HIDDEN_LABEL:
-                    r_dict[img] = os.path.join(images_dir, "vasr_images", QMARK_IMG)
+                    r_dict[img] = os.path.join(images_dir, "vasr_images", self.QMARK_IMG)
                 else:
                     r_dict[img] = os.path.join(images_dir, "vasr_images", r_dict[img])
             r_dict["A"] = r_dict['A_img']