docs: def pexpireat(self, key, timestamp):
          """:meth:`~tredis.RedisClient.pexpireat` has the same effect and
          semantic as :meth:`~tredis.RedisClient.expireat`, but the Unix time
          at which the key will expire is specified in milliseconds instead of
          seconds.
  
          .. note::
  
             **Time complexity**: ``O(1)``
  
          :param key: The key to set an expiration for
          :type key: :class:`str`, :class:`bytes`
          :param int timestamp: The expiration UNIX epoch value in milliseconds
          :rtype: bool
          :raises: :exc:`~tredis.exceptions.RedisError`
  
          """
          return self._execute(
              [b'PEXPIREAT', key,
               ascii(timestamp).encode('ascii')], 1)