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Solve the following problem using Python, implementing the functions described below, one line at a time
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<USER_TASK:>
Description:
 def basic_register(username, password, password2):
 """ Register a user and session, and then return the session_key and user. """

    if password != password2:
        raise InvalidInput(password={'message': "Passwords do not match"},
                           username={'value': username})
    user = User.objects.create_user(username, password)
    return create_session(user.username, password)