Is there a way to add a list of users to a team?

Say I am the team admin and would directly need to add users to the team. Is this possible?
Create new user api only gives me userid if the user has not logged in yet to mattermost. This is a problem because if the user has already logged in then it will fai and give me error as user has already logged inl.
Is there a way to retrieve userid by checking the email address?