Steve Clift pointed out that 'file' allows a netloc.

gvanrossum · gvanrossum · commit 974e32d910c2 · 1999-02-22T15:38:46.000Z
diff --git a/Lib/urlparse.py b/Lib/urlparse.py
@@ -10,6 +10,7 @@
 		 'https', 'shttp',
 		 'prospero', '']
 uses_netloc = ['ftp', 'http', 'gopher', 'nntp', 'telnet', 'wais',
+	       'file',
 	       'https', 'shttp', 'snews',
 	       'prospero', '']
 non_hierarchical = ['gopher', 'hdl', 'mailto', 'news', 'telnet', 'wais',
