added default for demo

SPIDER.py

@@ -63,6 +63,7 @@ MIN_IVD = 0
 MAX_IVD = 9
 DEFAULT_SCAN_TYPES = ['t1', 't2', 't2_SPACE']
 DEFAULT_RESIZE = (512, 512, 30)
+DEMO_SUBSET_N = 10
 
 _CITATION = """\
 @misc{vandergraaf2023lumbar,
@@ -404,12 +405,12 @@ class SPIDER(datasets.GeneratorBasedBuilder):
 
         # DEMO configuration: subset first 10 examples
         if self.config.name == "demo":
-            train_image_files = train_image_files[:10]
-            train_mask_files = train_mask_files[:10]
-            validate_image_files = validate_image_files[:10]
-            validate_mask_files = validate_mask_files[:10]
-            test_image_files = test_image_files[:10]
-            test_mask_files = test_mask_files[:10]
+            train_image_files = train_image_files[:DEMO_SUBSET_N]
+            train_mask_files = train_mask_files[:DEMO_SUBSET_N]
+            validate_image_files = validate_image_files[:DEMO_SUBSET_N]
+            validate_mask_files = validate_mask_files[:DEMO_SUBSET_N]
+            test_image_files = test_image_files[:DEMO_SUBSET_N]
+            test_mask_files = test_mask_files[:DEMO_SUBSET_N]
 
         return [
             datasets.SplitGenerator(