code: def firstUrn(resource):
          
          resource = xmlparser(resource)
          urn = resource.xpath("//ti:reply/ti:urn/text()", namespaces=XPATH_NAMESPACES, magic_string=True)
  
          if len(urn) > 0:
              urn = str(urn[0])
              return urn.split(":")[-1]
docs: Parse a resource to get the first URN
  
          :param resource: XML Resource
          :type resource: etree._Element
          :return: Tuple representing previous and next urn
          :rtype: str