Python 3.8.5 FTPS connection - python-3.x

Question

I'm trying to do a FTPS (or FTP) connection to a FTP server. This is done on Python 3.8.5 32 bit via Visual Studio Code.
Here is the code:
import ftplib
session = ftplib.FTP_TLS('server address')
#session.connect ('server address', 991)
session.login(user='username',passwd='password')
#session.prot_p()
session.set_pasv(True)
session.cwd("files")
print(session.pwd())
filename = "ftpTest.txt"
my_file = open('filepath\\ftpTest.txt', 'wb') # Open a local file to store the downloaded file
session.retrbinary('RETR ' + filename, my_file.write, 1024)
session.quit()
I am able to get the session.pwd (which display /files) but the connection timeout at line 11 (session.retrbinary) in approximately 22 sec with the following error:
Exception has occurred: TimeoutError
[WinError 10060] A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond
I had tried setting session.set_pasv to both True and False following Python ftplib timing out. Setting it True raised the TimeoutError and setting it False raise the following error at line 11:
Exception has occurred: error_perm
500 Illegal PORT command
and also tried setting a different port (991) following Python SSL FTP connection timing out and it raised the Timeout Error at line 3.
Using FTP without TLS raised the following error at line 4 (session.login):
Exception has occurred: error_perm
530 Non-anonymous sessions must use encryption.
Turning off my McAfee LiveSafe firewall didnt help either.
Btw file transfer works with Filezilla, was able to freely transfer.

Answer 1

Setting up the secure data connection and changing the session af to INET6 seemed to work for me. This was suggested to me by a colleague, and as to why it works is beyond me. If anyone can provide a proper explanation, please do.
Code:
session.login(user='username',passwd='password')
session.prot_p()
session.af = socket.AF_INET6