title: Telegram bot returning null
body: <p>I am trying to modify code from this <a href="https://djangostars.com/blog/how-to-create-and-deploy-a-telegram-bot/" rel="noreferrer">Webpage</a>:
  The modified code is as below:</p>
  
  <pre><code>import pandas as pd
  from pandas import datetime
  from pandas import DataFrame as df
  import matplotlib
  from pandas_datareader import data as web
  import matplotlib.pyplot as plt
  import datetime
  
  
  import requests  
  from bottle import (  
      run, post, response, request as bottle_request
  )
  
  BOT_URL = 'https://api.telegram.org/bot------------------/' 
  
  
  def get_chat_id(data):  
      """
      Method to extract chat id from telegram request.
      """
      chat_id = data['message']['chat']['id']
  
      return chat_id
  
  def get_message(data):  
      """
      Method to extract message id from telegram request.
      """
      message_text = data['message']['text']
  
      return message_text
  
  def send_message(prepared_data):  
      """
      Prepared data should be json which includes at least `chat_id` and `text`
      """ 
      message_url = BOT_URL + 'sendMessage'
      requests.post(message_url, json=prepared_data)  # don't forget to make import requests lib
  
  
  def get_ticker(text):  # &lt;-- **added this function and removed a function called `def change_text_message(text)`**;
      stock = f'text'
      start = datetime.date(2000,1,1)
      end = datetime.date.today()
      data = web.DataReader(stock, 'yahoo',start, end)
      plot = data.plot(y='Open')
      return plot
  
  
  def prepare_data_for_answer(data):  
      answer = get_ticker(get_message(data))
  
      json_data = {
          "chat_id": get_chat_id(data),
          "text": answer,
      }
  
      return json_data
  
  @post('/')
  def main():  
      data = bottle_request.json
  
      answer_data = prepare_data_for_answer(data)
      send_message(answer_data)  # &lt;--- function for sending answer
  
      return response  # status 200 OK by default
  </code></pre>
  
  <p>I have separated the code which I have modified with space above and below. At this point I am getting a text <code>null</code>, how can I fix this so when I enter a ticker, it returns the chart of the ticker? I am not sure the chart could be returned or if the only text could be sent back. The function which was added does work if run separately but just not here. </p>