Message 334043 - Python tracker

The “urllib.parse” module generally follows RFC 3986, which does not allow a literal backslash in the “userinfo” part:

userinfo = *( unreserved / pct-encoded / sub-delims / ":" )
unreserved = ALPHA / DIGIT / "-" / "." / "_" / "~"
pct-encoded = "%" HEXDIG HEXDIG
sub-delims = "!" / "$" / "&" / "'" / "(" / ")" / "*" / "+" / "," / ";" / "="

The RFC does not allow a backslash in the host name, path, query or fragment either. That is why I said the URL is not valid.