code: def _get_properties(self, fldstr):
          
          prop2val = {}
          props = self._rd_fld_vals("Properties", fldstr, False)  # Get set
          go_evidence = None
          for prop in props:
              # There can be more properties than 'go_evidence',
              # but currently we see only 'go_evidence'.
              # Upon encountering updates, evaluate and update code to support ...
              if prop[:12] == 'go_evidence=':
                  assert go_evidence is None, "MORE THAN ONE EVIDENCE CODE FOUND"
                  go_evidence = prop[12:]
              else:
                  assert False, "UNPROGRAMMED PROPERTY({P})".format(P=prop)
          ## TBD: Is 'go_evidence' still used? Replaced by ECO? And eco2group
          ## assert go_evidence is not None, "go_evidence == None"
          ## prop2val['go_evidence'] = go_evidence
          if go_evidence is not None:
              prop2val['go_evidence'] = go_evidence
          return prop2val
docs: Return optional Annotation Properties (0 or greater).