Update app.py

app.py

@@ -169,6 +169,7 @@ def infer(pm):
             _do.append(f'{p1}')
         posi = " ".join(_do)
 
+        if neg == "" or pm["i"] == None or posi == ""
         out = Piper(pm["i"],posi,neg,pm["m"])
         export_to_gif(out.frames[0],name,fps=fps)
         return name