def get(self, key, **kwargs):
        """
        Get the value of a key from etcd.

        example usage:

        .. code-block:: python

            >>> import etcd3
            >>> etcd = etcd3.client()
            >>> etcd.get('/thing/key')
            'hello world'

        :param key: key in etcd to get
        :param serializable: whether to allow serializable reads. This can
            result in stale reads
        :returns: value of key and metadata
        :rtype: bytes, ``KVMetadata``
        """
        range_response = self.get_response(key, **kwargs)
        if range_response.count < 1:
            return None, None
        else:
            kv = range_response.kvs.pop()
            return kv.value, KVMetadata(kv, range_response.header)