Update app.py

app.py

@@ -1,23 +1,22 @@
 import gradio as gr
 import os
 
-
 def load_mesh(mesh_file_name):
-    return mesh_file_name
-
+    if os.path.exists(mesh_file_name):
+        return mesh_file_name
+    return None
 
 demo = gr.Interface(
     fn=load_mesh,
     inputs=gr.Model3D(),
-    outputs=gr.Model3D(
-            clear_color=[0.0, 0.0, 0.0, 0.0],  label="3D Model"),
+    outputs=gr.Model3D(clear_color=[0.0, 0.0, 0.0, 0.0], label="3D Model"),
     examples=[
-        [os.path.join(os.path.dirname(__file__), "files/model1.glb")],
-        [os.path.join(os.path.dirname(__file__), "files/model2.glb")],
-        [os.path.join(os.path.dirname(__file__), "files/model3.glb")],
-        [os.path.join(os.path.dirname(__file__), "files/model4.glb")],
+        ["files/model1.glb"],
+        ["files/model2.glb"],
+        ["files/model3.glb"],
+        ["files/model4.glb"],
     ],
 )
 
 if __name__ == "__main__":
-    demo.launch()
+    demo.launch()