code: def set_default_proxy(cls, value):
          
          if value is None:
              cls.DEFAULT_PROXY = None
          else:
              scheme, host, port = get_hostname_parameters_from_url(value)
              cls.DEFAULT_PROXY = "%s://%s:%s" % (scheme, host, port)
docs: Default: None (no proxy)
  
          A string that will be used to tell each request must be sent through this proxy server.
          Use the scheme://hostname:port form.
          If you need to use a proxy, you can configure individual requests with the proxies argument to any request
          method.