How to verify github webhooks

verify_github.py

# Mostly cribbed from https://github.com/carlos-jenkins/python-github-webhooks/blob/759b67e3af8ed7334467b7d359cd00a10b0ac3c7/webhooks.py#L73
import hmac

def verify_github_webhook(secret, hub_signature_header, request_body):
    sha_name, sha_value = hub_signature_header.split('=')
    if sha_name != 'sha1':
        raise ValueError('Unknown signature algorithm')
        
    mac = hmac.new(secret.encode('utf-8'), msg=request_body, digestmod='sha1')
    if not hmac.compare_digest(str(mac.hexdigest()), str(sha_value)):
        print('Invalid signatures {}, {}', mac.hexdigest(), sha_value)
        raise ValueError('Incorrect webhook signature')
        
    return True