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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 convert_none(key, val, attr_type, attr={}, cdata=False):
 """Converts a null value into an XML element"""

    LOG.info('Inside convert_none(): key="%s"' % (unicode_me(key)))

    key, attr = make_valid_xml_name(key, attr)

    if attr_type:
        attr['type'] = get_xml_type(val)
    attrstring = make_attrstring(attr)
    return '<%s%s></%s>' % (key, attrstring, key)