How to teach Wordpress engine to be friends with Proxy? Easy!

I am developing a local corporate WordPress site. The company does not have direct access to the Internet, all work through a proxy server.

To automatically update the kernel and plugins (and some other functions), in order to avoid the message “WP HTTP Error: couldn't connect to host” or even 500 errors on IIS 7 (Windows 2008), I had a need to teach Wordpress to make friends with proxy.

Search on the Internet gave nothing. Naturally, the fact that I did not find something, does not mean that it is not on the Internet. At least there is no description in the Codex. And I had to look into the engine code, and as it turned out, this function is provided there and it works perfectly for itself. What I want to share with you.
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Decision

To do this, you must add at least two lines to any place in the ./wp-config.php file

define(WP_PROXY_HOST, 'localhost'); //
define(WP_PROXY_PORT, 3128); //

And two more, if the proxy requires authorization:

define(WP_PROXY_USERNAME, 'username');
define(WP_PROXY_PASSWORD, 'password');

That's all. Tested on versions 3.1+.