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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def setex(self, key, seconds, value):
 """Set key to hold the string value and set key to timeout after a given number of seconds. :meth:`~tredis.RedisClient.setex` is atomic, and can be reproduced by using :meth:`~tredis.RedisClient.set` and :meth:`~tredis.RedisClient.expire` inside an :meth:`~tredis.RedisClient.multi` / :meth:`~tredis.RedisClient.exec` block. It is provided as a faster alternative to the given sequence of operations, because this operation is very common when Redis is used as a cache. An error is returned when seconds is invalid. .. versionadded:: 0.2.0 .. note:: **Time complexity**: ``O(1)`` :param key: The key to set :type key: :class:`str`, :class:`bytes` :param int seconds: Number of seconds for TTL :param value: The value to set :type value: :class:`str`, :class:`bytes` :rtype: bool :raises: :exc:`~tredis.exceptions.RedisError` """

        return self._execute([b'SETEX', key, ascii(seconds), value], b'OK')