Get Bitcoin Wallet balance with Python On a tutorial in Youtube
it uses pybitcointools. Upon searching it's github repository, I have found that it was not maintained anymore. Are there any alternative to this library which can get wallet balance?

Thank you.
Assuming you have a Bitcoin node to execute RPC calls against (i.e. you're running bitcoind with the RPC turned on), you can do this rather simply with pyjsonrpc:

#!/usr/bin/env python
from pyjsonrpc import ServiceProxy

bitcoin = ServiceProxy("http://127.0.0.1:8332")  # this is your bitcoind node and RPC port
bitcoin.username = 'testuser'  # rpcuser
bitcoin.password = 'testpass'  # rpcpassword
print(bitcoin.getbalance())