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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 filechunk(f, chunksize):
 """Iterator that allow for piecemeal processing of a file."""

    while True:
        chunk = tuple(itertools.islice(f, chunksize))
        if not chunk:
            return
        yield np.loadtxt(iter(chunk), dtype=np.float64)