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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 subpartition(quadtree, nmin, nmax):
 """ Recursive core of the ``QuadTree.partition`` method. Just five lines of code, amazingly. Parameters quadtree : QuadTree object instance The QuadTree object instance being partitioned. nmin : int The splitting threshold. If this is not met this method will return a listing containing the root tree alone. Returns ------- A (probably nested) list of QuadTree object instances containing a number of points respecting the threshold parameter. """

    subtrees = quadtree.split()
    if quadtree.n > nmax:
        return [q.partition(nmin, nmax) for q in subtrees]
    elif any([t.n < nmin for t in subtrees]):
        return [quadtree]
    else:
        return [q.partition(nmin, nmax) for q in subtrees]