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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 kids(tup_tree):
 """ Return a list with the child elements of tup_tree. The child elements are represented as tupletree nodes. Child nodes that are not XML elements (e.g. text nodes) in tup_tree are filtered out. """

    k = tup_tree[2]
    if k is None:
        return []
    # pylint: disable=unidiomatic-typecheck
    return [x for x in k if type(x) == tuple]