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11.5.1 Request Objects

The following methods describe all of `Request`'s public interface, and so all must be overridden in subclasses.

`add_data`(data)
  Set the `Request` data to data. This is ignored by all handlers except HTTP handlers -- and there it should be an application/x-www-form-encoded buffer, and will change the request to be `POST` rather than `GET`.

`has_data`()
  Return whether the instance has a non-`None` data.

`get_data`()
  Return the instance's data.

`add_header`(key, val)
  Add another header to the request. Headers are currently ignored by all handlers except HTTP handlers, where they are added to the list of headers sent to the server. Note that there cannot be more than one header with the same name, and later calls will overwrite previous calls in case the key collides. Currently, this is no loss of HTTP functionality, since all headers which have meaning when used more than once have a (header-specific) way of gaining the same functionality using only one header.

`get_full_url`()
  Return the URL given in the constructor.

`get_type`()
  Return the type of the URL -- also known as the scheme.

`get_host`()
  Return the host to which a connection will be made.

`get_selector`()
  Return the selector -- the part of the URL that is sent to the server.

`set_proxy`(host, type)
  Prepare the request by connecting to a proxy server. The host and type will replace those of the instance, and the instance's selector will be the original URL given in the constructor.