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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 overlap(xl1, yl1, nx1, ny1, xl2, yl2, nx2, ny2):
 """ Determines whether two windows overlap """

    return (xl2 < xl1+nx1 and xl2+nx2 > xl1 and
            yl2 < yl1+ny1 and yl2+ny2 > yl1)