How to use the slixmpp.exceptions.XMPPError function in slixmpp

def _recv_data(self, stanza):
        new_seq = stanza['ibb_data']['seq']
        if new_seq != (self.recv_seq + 1) % 65535:
            self.close()
            raise XMPPError('unexpected-request')
        self.recv_seq = new_seq

        data = stanza['ibb_data']['data']
        if len(data) > self.block_size:
            self.close()
            raise XMPPError('not-acceptable')

        self.recv_queue.put_nowait(data)
        self.xmpp.event('ibb_stream_data', self)

        if isinstance(stanza, Iq):
            stanza.reply().send()

self.extension_args = extension_args

    def format(self):
        """
        Format the error in a simple user-readable string.
        """
        text = [self.etype, self.condition]
        if self.text:
            text.append(self.text)
        if self.extension:
            text.append(self.extension)
        # TODO: handle self.extension_args
        return ': '.join(text)


class IqTimeout(XMPPError):

    """
    An exception which indicates that an IQ request response has not been
    received within the alloted time window.
    """

    def __init__(self, iq):
        super().__init__(
                condition='remote-server-timeout',
                etype='cancel')

        #: The :class:`~slixmpp.stanza.iq.Iq` stanza whose response
        #: did not arrive before the timeout expired.
        self.iq = iq

def _handle_request(self, iq):
        profile = iq['si']['profile']
        sid = iq['si']['id']

        if not sid:
            raise XMPPError(etype='modify', condition='bad-request')
        if profile not in self._profiles:
            raise XMPPError(
                etype='modify',
                condition='bad-request',
                extension='bad-profile',
                extension_ns=SI.namespace)

        neg = iq['si']['feature_neg']['form'].get_fields()
        options = neg['stream-method']['options'] or []
        methods = []
        for opt in options:
            methods.append(opt['value'])
        for method in methods:
            if method in self._methods:
                supported = True
                break
        else:
            raise XMPPError('bad-request',

etype='modify',
                condition='bad-request',
                extension='bad-profile',
                extension_ns=SI.namespace)

        neg = iq['si']['feature_neg']['form'].get_fields()
        options = neg['stream-method']['options'] or []
        methods = []
        for opt in options:
            methods.append(opt['value'])
        for method in methods:
            if method in self._methods:
                supported = True
                break
        else:
            raise XMPPError('bad-request',
                    extension='no-valid-streams',
                    extension_ns=SI.namespace)

        selected_method = None
        log.debug('Available: %s', methods)
        for order, method, plugin in self._methods_order:
            log.debug('Testing: %s', method)
            if method in methods:
                selected_method = method
                break

        receiver = iq['to']
        sender = iq['from']

        self.api['add_pending'](receiver, sid, sender, {
            'response_id': iq['id'],

async def _start(self, event):
        try:
            vcard = await self.xmpp['xep_0054'].get_vcard(self.xmpp.boundjid.bare)
            data = vcard['vcard_temp']['PHOTO']['BINVAL']
            if not data:
                new_hash = ''
            else:
                new_hash = hashlib.sha1(data).hexdigest()
            self.api['set_hash'](self.xmpp.boundjid, args=new_hash)
        except XMPPError:
            log.debug('Could not retrieve vCard for %s', self.xmpp.boundjid.bare)

def get_data(self):
        text = self.xml.text
        if not text:
            raise XMPPError('not-acceptable', 'IBB data element is empty.')
        b64_data = text.strip()
        if VALID_B64.match(b64_data).group() == b64_data:
            return from_b64(b64_data)
        else:
            raise XMPPError('not-acceptable')

print('Could not find file: %s' % self.filepath)
            return self.disconnect()

        avatar = avatar_file.read()

        avatar_type = 'image/%s' % imghdr.what('', avatar)
        avatar_id = self['xep_0084'].generate_id(avatar)
        avatar_bytes = len(avatar)

        avatar_file.close()

        used_xep84 = False

        print('Publish XEP-0084 avatar data')
        result = await self['xep_0084'].publish_avatar(avatar)
        if isinstance(result, XMPPError):
            print('Could not publish XEP-0084 avatar')
        else:
            used_xep84 = True

        print('Update vCard with avatar')
        result = await self['xep_0153'].set_avatar(avatar=avatar, mtype=avatar_type)
        if isinstance(result, XMPPError):
            print('Could not set vCard avatar')

        if used_xep84:
            print('Advertise XEP-0084 avatar metadata')
            result = await self['xep_0084'].publish_avatar_metadata([
                {'id': avatar_id,
                 'type': avatar_type,
                 'bytes': avatar_bytes}
                # We could advertise multiple avatars to provide

avatar_bytes = len(avatar)

        avatar_file.close()

        used_xep84 = False

        print('Publish XEP-0084 avatar data')
        result = await self['xep_0084'].publish_avatar(avatar)
        if isinstance(result, XMPPError):
            print('Could not publish XEP-0084 avatar')
        else:
            used_xep84 = True

        print('Update vCard with avatar')
        result = await self['xep_0153'].set_avatar(avatar=avatar, mtype=avatar_type)
        if isinstance(result, XMPPError):
            print('Could not set vCard avatar')

        if used_xep84:
            print('Advertise XEP-0084 avatar metadata')
            result = await self['xep_0084'].publish_avatar_metadata([
                {'id': avatar_id,
                 'type': avatar_type,
                 'bytes': avatar_bytes}
                # We could advertise multiple avatars to provide
                # options in image type, source (HTTP vs pubsub),
                # size, etc.
                # {'id': ....}
            ])
            if isinstance(result, XMPPError):
                print('Could not publish XEP-0084 metadata')

async def on_avatar(self, msg):
        print("Received avatar update from %s" % msg['from'])
        metadata = msg['pubsub_event']['items']['item']['avatar_metadata']
        for info in metadata['items']:
            if not info['url']:
                try:
                    result = await self['xep_0084'].retrieve_avatar(msg['from'].bare, info['id'],
                                                                         timeout=5)
                except XMPPError:
                    print("Error retrieving avatar for %s" % msg['from'])
                    return

                avatar = result['pubsub']['items']['item']['avatar_data']

                filetype = FILE_TYPES.get(metadata['type'], 'png')
                filename = 'avatar_%s_%s.%s' % (msg['from'].bare, info['id'], filetype)
                with open(filename, 'wb+') as img:
                    img.write(avatar['value'])
            else:
                # We could retrieve the avatar via HTTP, etc here instead.
                pass

if session:
            handler = session['next']
            interfaces = session['interfaces']
            results = []
            for stanza in iq['command']['substanzas']:
                if stanza.plugin_attrib in interfaces:
                    results.append(stanza)
            if len(results) == 1:
                results = results[0]

            session = handler(results, session)

            self._process_command_response(iq, session)
        else:
            raise XMPPError('item-not-found')