Enhancement to support FTP connection with NAT scenario

Feature or enhancement

Proposal:

Some of new FTP servers are responding with 229 Entering Extended passive mode response when PASV command is sent.. Because of this sendcmd('PASV') is sending error though it's a accepted response. Tested with filezilla manually where it's accepting the same. So we need to make changes in ftplib to accept & parse Extended mode with 'PASV' command. Please help to review and merge.

Has this already been discussed elsewhere?

This is a minor feature, which does not need previous discussion elsewhere

Links to previous discussion of this feature:

No response

Linked PRs

• gh-127477
• gh-150236

从 Python 的 ftplib 处理 sendcmd('PASV') 的方式入手，并审查 gh-127477 和 gh-150236 中的相关工作。完成的标准是：针对 FTP NAT 场景解析被接受的 229 响应，同时不破坏现有的 PASV 行为。