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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 _requires_login(func: Callable) -> Callable: """Decorator to raise an exception if herewith-decorated function is called without being logged in"""

    @wraps(func)
    def call(instaloader, *args, **kwargs):
        if not instaloader.context.is_logged_in:
            raise LoginRequiredException("--login=USERNAME required.")
        return func(instaloader, *args, **kwargs)
    # pylint:disable=no-member
    call.__doc__ += ":raises LoginRequiredException: If called without being logged in.\n"
    return call