Issue: Data from Websocket to Python dataframes

from kiteconnect import WebSocket
import datetime
import pandas as pd

#columns in data frame
df_cols = ["Token", "LTP", "Volume"]

data_frame = pd.DataFrame(data=[],columns=df_cols, index=[])

def on_tick(ticks, ws):
	global data_frame, df_cols

	data = dict() #keeps extracted tick data

	for tick in ticks:
		token = tick["instrument_token"]
		ltp = tick["last_price"]
		volume = tick["volume"]
		timestamp = str(datetime.datetime.now().time())

		data[timestamp] = [token, ltp, volume]

	tick_df = pd.DataFrame(data.values(), columns=df_cols, index=data.keys()) #convert data to a DataFrame
	data_frame = data_frame.append(tick_df) # append to existing

	print "DataFrame: \n", data_frame


def on_connect(ws):
	print "Connected"
	ws.subscribe([53480455]) #subscribe for ticks

#initialize
kws = WebSocket("api_key", "public_token", "user_id")
kws.on_tick = on_tick
kws.on_connect = on_connect
kws.connect()

1) what if there are multiple scrips? what should I change in the above code?

2) how to use this data stored in dataframes to create ohlc 15min candles