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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 assignLeafRegisters(inodes, registerMaker):
 """Assign new registers to each of the leaf nodes. """

    leafRegisters = {}
    for node in inodes:
        key = node.key()
        if key in leafRegisters:
            node.reg = leafRegisters[key]
        else:
            node.reg = leafRegisters[key] = registerMaker(node)