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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 sort_elements_by_child_values(obj_pyxb, child_name_list):
 """In-place sort simple or complex elements in a PyXB object by values they contain in child elements. Args: obj_pyxb: PyXB object child_name_list: list of str List of element names that are direct children of the PyXB object. """

    obj_pyxb.sort(key=lambda x: [get_auto(getattr(x, n)) for n in child_name_list])