e attempt to reconnect</span>. The function will be invoked
 with three arguments: the close reason code, the channel name and the raw <code>CloseEvent</code> itself.
 <span class="changed_modified_4_0">Note that this will also be invoked when the close is caused by an
 error and that you can inspect the close reason code if an actual connection error occurred and which one (i.e.
 when the code is not 1000 or 1008)</span>. See also <a href="http://tools.ietf.org/html/rfc6455#section-7.4.1">RFC 6455
 section