max_tokens = gr.Slider(minimum=50, maximum=4000, value=1000, label="Max Tokens")

app.py

@@ -39,7 +39,7 @@ with gr.Blocks() as demo:
             # basic inputs
             gr.Markdown("## Basic Inputs")
             model = gr.Radio(["gpt-4-1106-preview", "gpt-3.5-turbo"], label="Model")
-            max_tokens = gr.Slider(minimum=50, maximum=4000, default=1000, label="Max Tokens")
+            max_tokens = gr.Slider(minimum=50, maximum=4000, value=1000, label="Max Tokens")
             sys_content_input = gr.Textbox(label="System Prompt", value="You are an English teacher who is practicing with me to improve my English writing skill.")
             scenario_input = gr.Textbox(label="Scenario")
             eng_level_input = gr.Radio(["beginner", "intermediate", "advanced"], label="English Level")