Guzzle Error with SDK 8.4.2 & php 7.4.3

[Colir]

Uncaught Error: Call to undefined method GuzzleHttp\Utils::chooseHandler()

Hi,
I've just installed SDK 8.4.2, and starting to develop Custom code to send transactional emails.

On my first try, I got this error
Uncaught Error: Call to undefined method GuzzleHttp\Utils::chooseHandler()

Would anyone be able to help me?

Thank you.

[Colir]

ok, I've found the problem.
It's due to another install of Guzzle in another folder loaded with the autoloader.

But how I can isolate Guzzle use on different folders, if I need different versions of Guzzle?

thank you