return empty figure

app.py

@@ -61,8 +61,22 @@ class BinPacking:
         return self
 
     def visualize(self):
+        fig = go.Figure()
+        fig.update_layout(
+            autosize=False,
+            width=500,
+            height=500,
+            margin=dict(
+                l=50,
+                r=50,
+                b=100,
+                t=100,
+                pad=4
+            ),
+            paper_bgcolor="LightSteelBlue",
+        )
         if self.pgrp == None:
-            return None
+            return fig
 
         _, thresh = cv2.threshold(self.imgray, 127, 255, 0)
         contours, _ = cv2.findContours(thresh, cv2.RETR_TREE, cv2.CHAIN_APPROX_SIMPLE)
@@ -74,7 +88,6 @@ class BinPacking:
                 transformedPoints.append([None,None])
             transformedPoints.append([None,None])
 
-        fig = go.Figure()
         fig.add_trace(go.Scatter(
             x=[0, self.width, self.width, 0, 0],
             y=[0, 0, self.height, self.height, 0],
@@ -88,19 +101,6 @@ class BinPacking:
             mode="lines",
             textposition="bottom right",
         )) 
-        fig.update_layout(
-            autosize=False,
-            width=500,
-            height=500,
-            margin=dict(
-                l=50,
-                r=50,
-                b=100,
-                t=100,
-                pad=4
-            ),
-            paper_bgcolor="LightSteelBlue",
-        )
         return fig
 
 
@@ -137,7 +137,6 @@ if __name__ == "__main__":
                 
             with gr.Column():
                 plot_output = gr.Plot()
-                total = gr.Number(label="Total")
                 text = gr.Text()
                 
         fit.click(fn=process, inputs=[width, height, scale, image], outputs=[plot_output, text])