Fix examples/telnet/hello-world.py example.

Author: jonathanslenders

examples/telnet/hello-world.py

@@ -10,7 +10,7 @@
 
 from prompt_toolkit.contrib.telnet.server import TelnetServer
 from prompt_toolkit.eventloop import get_event_loop
-from prompt_toolkit.shortcuts import clear, prompt
+from prompt_toolkit.shortcuts import PromptSession, clear
 
 # Set up logging
 logging.basicConfig()
@@ -22,7 +22,8 @@ async def interact(connection):
     connection.send("Welcome!\n")
 
     # Ask for input.
-    result = await prompt(message="Say something: ", async_=True)
+    session = PromptSession()
+    result = await session.prompt_async(message="Say something: ")
 
     # Send output.
     connection.send(f"You said: {result}\n")