def METHOD_NAME(xml,eventType,source):
    from xml.dom.minidom import parse
    wrappedCont = parse(xml)
    content = wrappedCont.getElementsByTagName('dataFiles')[0]
    byType  = content.getElementsByTagName(eventType)
    if len(byType) == 0:
        return None
    fnames  = byType[0].getElementsByTagName('file')
    for fname in fnames:
        node = (fname.childNodes)[0] #childNodes should be a one element array
        source.fileNames.append(str(node.nodeValue).replace('\n','').replace('\t',''))