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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 range_minmax(ranges):
 """ Returns the span of a collection of ranges where start is the smallest of all starts, and end is the largest of all ends. (10, 100) """

    rmin = min(ranges)[0]
    rmax = max(ranges, key=lambda x: x[1])[1]
    return rmin, rmax