DNS lookup attempts for IP hostnames

[JustAnotherArchivist]

When fetching from an IP URL, wpull still performs a DNS lookup. This can be seen in the verbose log output (Lookup address):

$ wpull --debug --tries 1 http://127.0.0.1/
[...]
INFO Fetching ‘http://127.0.0.1/’.
DEBUG Client fetch request <Request(GET, http://127.0.0.1/, HTTP/1.1)>.
DEBUG Check out ('127.0.0.1', 80, False)
DEBUG Lookup address 127.0.0.1.
DEBUG Get item from source
DEBUG Resolved addresses: [_AddressInfo(ip_address='127.0.0.1', family=<AddressFamily.AF_INET: 2>, flow_info=None, scope_id=None)].
[...]

Notably, this appears to attempt an actual lookup over the network with dnspython. I only noticed this because I happened to be on a network where most traffic was being dropped (not refused or similar, just silently dropped, à la iptables DROP policy), including DNS. This caused wpull to hang on the DNS lookup until the timeout failed the retrieval.

wpull should obviously not be doing DNS lookups for IPs.