def test_defaultHosts(self):
        """
        L{client.createResolver} returns a L{resolve.ResolverChain} including a
        L{hosts.Resolver} using I{/etc/hosts} if no alternate hosts file is
        specified.
        """
        with AlternateReactor(Clock()):
            resolver = client.createResolver()
        self._hostsTest(resolver, b"/etc/hosts")

        L{client.createResolver} returns a L{resolve.ResolverChain} including a
        L{hosts.Resolver} using I{/etc/hosts} if no alternate hosts file is
        specified.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/names/test/test_client.py