Couple of functions for handling linked marc fields in iii xrecord format.

linked880iiixrec.py

#pass in elementree tree obj
#pass call linked_value('245', subfields=['a', 'c'])

def linked_fields(self):
  linked_fields = []
  for field in self.var_fields:
    rec_tag = field.findtext('MARCINFO/MARCTAG')
    if '880' == rec_tag:
      linked_fields.append((field.findall('MARCSUBFLD'), field))
  return linked_fields

def linked_value(self, tag, subfields=None):
  return_text = []
  for info in self.lf():
    field_data = info[1]
    indicators = info[0]
    for indicator in indicators:
      if indicator.find('SUBFIELDINDICATOR').text == '6':
        if indicator.find('SUBFIELDDATA').text.split('-')[0] == tag:
        #get the subfields for this 880 tag
        these_subfields = field_data.findall('MARCSUBFLD')
        #iterate through the sfs
        for tag_cells in these_subfields:
          sf_tag = tag_cells.find('SUBFIELDINDICATOR').text
          sf_text = tag_cells.find('SUBFIELDDATA').text
          if sf_tag in subfields:
            return_text.append(normalize(sf_text))
  return ' '.join(return_text)