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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 find_child_element(elm, child_local_name):
 """ Find an XML child element by local tag name. """

    for n in range(len(elm)):
        child_elm = elm[n]
        tag = etree.QName(child_elm)
        if tag.localname == child_local_name:
            return child_elm
    return None