Tidy examples and update licenses

telethon_examples/print_updates.py

@@ -1,12 +1,16 @@
 #!/usr/bin/env python3
-# A simple script to print all updates received
+# A simple script to print all updates received.
+# Import modules to access environment, sleep, write to stderr
 import os
 import sys
 import time
 
+# Import the client
 from telethon import TelegramClient
 
 
+# This is a helper method to access environment variables or
+# prompt the user to type them in the terminal if missing.
 def get_env(name, message, cast=str):
     if name in os.environ:
         return os.environ[name]
@@ -19,28 +23,23 @@ def get_env(name, message, cast=str):
             time.sleep(1)
 
 
-client = TelegramClient(
-    os.environ.get('TG_SESSION', 'printer'),
-    get_env('TG_API_ID', 'Enter your API ID: ', int),
-    get_env('TG_API_HASH', 'Enter your API hash: '),
-    proxy=None
-)
+# Define some variables so the code reads easier
+session = os.environ.get('TG_SESSION', 'printer')
+api_id = get_env('TG_API_ID', 'Enter your API ID: ', int)
+api_hash = get_env('TG_API_HASH', 'Enter your API hash: ')
+proxy = None  # https://github.com/Anorov/PySocks
 
 
-async def update_handler(update):
+# This is our update handler. It is called when a new update arrives.
+async def handler(update):
     print(update)
 
 
-client.add_event_handler(update_handler)
+# Use the client in a `with` block. It calls `start/disconnect` automatically.
+with TelegramClient(session, api_id, api_hash, proxy=proxy) as client:
+    # Register the update handler so that it gets called
+    client.add_event_handler(handler)
 
-'''You could also have used the @client.on(...) syntax:
-from telethon import events
-
-@client.on(events.Raw)
-async def update_handler(update):
-    print(update)
-'''
-
-with client.start():
+    # Run the client until Ctrl+C is pressed, or the client disconnects
     print('(Press Ctrl+C to stop this)')
     client.run_until_disconnected()