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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 append(x: T, xs: Iterable[T]) -> Iterator[T]: """ Append a value to an iterable. Parameters x An element of type T. xs An iterable of elements of type T. Returns ------- Iterator An iterator that yields elements of *xs*, then yields *x*. Examples -------- [2, 3, 1] """


    return chain(xs, [x])