'Initiate a basic file transfer by sending the URL of
a file or other resource.
Arguments:
url      -- The URL of the resource to transfer.
desc     -- An optional human readable description of the item
that is to be transferred.
ifrom    -- Specifiy the sender\'s JID.
block    -- If true, block and wait for the stanzas\' reply.
timeout  -- The time in seconds to block while waiting for
a reply. If None, then wait indefinitely.
callback -- Optional callback to execute when a reply is
received instead of blocking and waiting for
the reply.'

def send_oob(self, to, url, desc=None, ifrom=None, **iqargs):

    iq = self.xmpp.Iq()
    iq['type'] = 'set'
    iq['to'] = to
    iq['from'] = ifrom
    iq['oob_transfer']['url'] = url
    iq['oob_transfer']['desc'] = desc
    return iq.send(**iqargs)
