docs: def parse_relationship(document, xmlcontent, rel_type):
      """Parse relationship document.
  
      Relationships hold information like external or internal references for links.
  
      Relationships are placed in file '_rels/document.xml.rels'.
      """
  
      doc = etree.fromstring(xmlcontent)
  
      for elem in doc:
          if elem.tag == _name('{{{pr}}}Relationship'):
              rel = {'target': elem.attrib['Target'],
                     'type': elem.attrib['Type'],
                     'target_mode': elem.attrib.get('TargetMode', 'Internal')}
  
              document.relationships[rel_type][elem.attrib['Id']] = rel