Blockchain.com Market OHLC data API call

Question

I am following the documentation give by Blockchain. Successfully subscribe to the channel.

But how do I get the data? I want to retrieve historical data, and be able to receive real time data.

This is my python code:

#!/usr/bin/python
# Simple python websocket client
# https://github.com/websocket-client/websocket-client
from websocket import create_connection
options = {}
options['origin'] = 'https://exchange.blockchain.com'
url = "wss://ws.prod.blockchain.info/mercury-gateway/v1/ws"
ws = create_connection(url, **options)
#msg = '{"token": "sdwerdsf-bgft-345d-hfds-asdfghjkl", "action": "subscribe", "channel": "prices"}'


msg = """{"token": "sdwerdsf-bgft-345d-hfds-asdfghjkl",
        "action": "subscribe",
        "channel": "prices",
        "symbol": "BTC-USD",
        "granularity": 60
        }"""

ws.send(msg)
result =  ws.recv()
print(result)
# { "seqnum":0,
#   "event":"subscribed",
#   "channel":"auth",
#   "readOnly":false }
ws.close()

Response:

# ./blockchain-apitest.py
{"seqnum":0,"event":"subscribed","channel":"prices","symbol":"BTC-USD","granularity":60}