default installed global :class:`OpenerDirector` uses :class:`UnknownHandler` to
ensure this never happens).
+ In addition, default installed :class:`ProxyHandler` makes sure the requests
+ are handled through the proxy when they are set.
.. class:: ProxyHandler([proxies])
Cause requests to go through a proxy. If *proxies* is given, it must be a
- dictionary mapping protocol names to URLs of proxies. The default is to read the
- list of proxies from the environment variables :envvar:`<protocol>_proxy`.
+ dictionary mapping protocol names to URLs of proxies. The default is to read
+ the list of proxies from the environment variables
+ :envvar:`<protocol>_proxy`. If no proxy environment variables are set, in a
+ Windows environment, proxy settings are obtained from the registry's
+ Internet Settings section and in a Mac OS X environment, proxy information
+ is retrieved from from the OS X System Configuration Framework.
To disable autodetected proxy pass an empty dictionary.