Url parser is allowing only 'v' in the IPvFuture. As per the standards the 'v' could be case-insensitive as mentioned here

• urlparse('http://[v1fe.d:9]/') is valid
• urlparse('http://[V1fe.d:9]/') throws ValueError

while http://[V1fe.d:9]/ is also a valid IPvFuture hostname.

Checked in python version 3.11.4

Linked PRs

• gh-105708: 'V' could be case insensitive for IPvFuture hostnames #105709
• [3.15] gh-105708: 'V' could be case insensitive for IPvFuture hostnames (GH-105709) #153138
• [3.14] gh-105708: 'V' could be case insensitive for IPvFuture hostnames (GH-105709) #153139
• [3.13] gh-105708: 'V' could be case insensitive for IPvFuture hostnames (#5709) #153140