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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:
 async def get_user(username: str, api_key: str, **kwargs) -> User: """ Creates a new user, validate its credentials and returns it |funccoro| Args: username: username as specified on the challonge website api_key: key as found on the challonge `settings <https://challonge.com/settings/developer>`_ Returns: User: a logged in user if no exception has been raised Raises: APIException """

    new_user = User(username, api_key, **kwargs)
    await new_user.validate()
    return new_user