main.py

from telegram.ext import Updater, CommandHandler, MessageHandler, InlineQueryHandler, Filters
from telegram import InlineQueryResultArticle, InputTextMessageContent
from configparser import ConfigParser

# Ref: http://fygul.blogspot.com/2017/07/configparser.html
cfg = ConfigParser()
cfg.read('config.ini')
token = cfg['token']['key']

updater = Updater(token=token, use_context=True)
dispatcher = updater.dispatcher

# To catch commands like "/start"
def start(update, context):
    context.bot.send_message(chat_id=update.effective_chat.id, text="I'm a bot, please talk to me!")

start_handler = CommandHandler('start', start)
dispatcher.add_handler(start_handler)

# To repeat what the user said
def echo(update, context):
    context.bot.send_message(chat_id=update.effective_chat.id, text=update.message.text)

echo_handler = MessageHandler(Filters.text and (~Filters.command), echo)
dispatcher.add_handler(echo_handler)

# To capitalize what the user inputted after /caps
def caps(update, context):
    text_caps = ' '.join(context.args).upper()
    context.bot.send_message(chat_id=update.effective_chat.id, text=text_caps)

caps_handler = CommandHandler('caps', caps)
dispatcher.add_handler(caps_handler)

# To captialize words using inline mode
def inline_caps(update, context):
    query = update.inline_query.query
    if not query:
        return
    results = list()
    results.append(
        InlineQueryResultArticle(
            id=query.upper(),
            title='Caps',
            input_message_content=InputTextMessageContent(query.upper())
        )
    )
    context.bot.answer_inline_query(update.inline_query.id, results)

inline_caps_handler = InlineQueryHandler(inline_caps)
dispatcher.add_handler(inline_caps_handler)

# Unknown commands
def unknown(update, context):
    context.bot.send_message(chat_id=update.effective_chat.id, text="Sorry, I didn't understand that command.")

unknown_handler = MessageHandler(Filters.command, unknown)
dispatcher.add_handler(unknown_handler)

# To start the bot
updater.start_polling()
print("The bot is working.")

# To end the bot
updater.idle()
print("The bot is stopped.")