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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 confirm_user(user):
 """Confirms the specified user :param user: The user to confirm """

    if user.confirmed_at is not None:
        return False
    user.confirmed_at = _security.datetime_factory()
    _datastore.put(user)
    user_confirmed.send(app._get_current_object(), user=user)
    return True