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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 adam7_generate(width, height):
 """ Generate the coordinates for the reduced scanlines of an Adam7 interlaced image of size `width` by `height` pixels. Yields a generator for each pass, and each pass generator yields a series of (x, y, xstep) triples, each one identifying a reduced scanline consisting of pixels starting at (x, y) and taking every xstep pixel to the right. """


    for xstart, ystart, xstep, ystep in adam7:
        if xstart >= width:
            continue
        yield ((xstart, y, xstep) for y in range(ystart, height, ystep))