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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 filesizes(images):
 """Stat filesize of files. Args: images: stream of marv image files Returns: Stream of filesizes """

    # Pull each image and push its filesize
    while True:
        img = yield marv.pull(images)
        if img is None:
            break
        yield marv.push(img.size)