added functionally to chatbot

app.py

@@ -1,5 +1,15 @@
-import gradio as gr #abbreviate gradio
+import gradio as gr #abbreviate gradio, import lines go first
+
+def echo(message, history): #function for Gradio to call
+#Gradio passes arguments as parameters: the user's most recent input which is a string, i'm going to call it "message", and "history" which is the list of past messages
+#I have to put it in this order because Gradio will always past the current user input first and then the convo history  
+# however for now, this chatbot won't use the history parameter anyay
+    return message #returns what user types in
+
+# “I'm passing the function name 'echo' to ChatInterface, not 'echo()' with parentheses, because I want Gradio to call it later, not right now.”
+
 
 # defining chatbot
-chatbot = gr.ChatInterface() #using gradio to quickly build a chatbot UI (w/ convo history & user input)
+chatbot = gr.ChatInterface(echo) #using gradio to quickly build a chatbot UI (w/ convo history & user input)
+# passing echo for gradio to call, not w/ () because I want Gradio to call it later, not right now
 chatbot.launch() #launch chatbot