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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 leaf_list(cls, name, parent=None, interleave=None):
 """Create _list_ node for a leaf-list."""

        node = cls("_list_", parent, interleave=interleave)
        node.attr["name"] = name
        node.keys = None
        node.minEl = "0"
        node.maxEl = None
        node.occur = 3
        return node