Nope, from the code
def NetworkUp(self, host="8.8.8.8", port=53, timeout=2):
Port 53, DNS.
[edit]
Why not do the same thing, but to the nameservers defined in network settings? Nothing works without DNS resolution, so surely the most pragmatic approach is to connect to the defined nameserver rather than a hardcoded one?
I have no desire to go on a religious crusade here, I just thing the approach is flawed.