Re-subscribe to any channels and patterns previously subscribed to

def on_connect(self, connection):
        "Re-subscribe to any channels and patterns previously subscribed to"
        # NOTE: for python3, we can't pass bytestrings as keyword arguments
        # so we need to decode channel/pattern names back to unicode strings
        # before passing them to [p]subscribe.
        self.pending_unsubscribe_channels.clear()
        self.pending_unsubscribe_patterns.clear()
        if self.channels:
            channels = {}
            for k, v in iteritems(self.channels):
                channels[self.encoder.decode(k, force=True)] = v
            self.subscribe(**channels)
        if self.patterns:
            patterns = {}
            for k, v in iteritems(self.patterns):
                patterns[self.encoder.decode(k, force=True)] = v
            self.psubscribe(**patterns)