def signup(self, signup_data):

        study = signup_data.get("study", None)
        email = signup_data.get("email", None)
        username = signup_data.get("username", None)
        password = signup_data.get("password", None)
        self._validate_signup_data(study, email, username, password)
        self._validate_study(study)
        user_dao = UserDAO()
        user = user_dao.get_user_by_email(email)
        created_datetime = DateUtils.get_datetime_utc()
        if not user:

            user = user_dao.create(username, email, password, study, created_datetime)
        else:
            user["studies"].append({"username": username, "password":password, "id":study, "created_datetime": created_datetime} )
            user_dao.save(user)
        #Create a record in User Linked to the Study
        #Creadentials per Study?
        return  {"message": "Signed up."}