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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 fuse_list( mafs ):
 """ Try to fuse a list of blocks by progressively fusing each adjacent pair. """

    last = None
    for m in mafs:
        if last is None:
            last = m
        else:
            fused = fuse( last, m )
            if fused:
                last = fused
            else:
                yield last
                last = m
    if last:
        yield last