Snake in a dream symbolizes third eye.
To dream it can mean that you have special power of this third eye. It is possible that such dream is a reminder for you to use your super power more.
Also, it can indicate that your insightful thoughts are based on this power. Thus the dream is just a subconscious representation of it.
Third eye symbolism is fortunate and predicts successful happenings because of insightful seeings provided by third eye.