docs: def creds_display(creds: Union[dict, Sequence[dict]], filt: dict = None, filt_dflt_incl: bool = False) -> dict:
      """
      Find indy-sdk creds matching input filter from within input creds structure,
      sequence of cred-briefs/cred-infos, or cred-brief-dict.  Return human-legible summary.
  
      :param creds: creds structure, cred-brief/cred-info or sequence thereof,
          or cred-brief-dict; e.g., creds
  
      ::
  
          {
              "attrs": {
                  "attr0_uuid": [
                      {
                          "interval": null,
                          "cred_info": {
                              "attrs": {
                                  "attr0": "2",
                                  "attr1": "Hello",
                                  "attr2": "World"
                              },
                              "referent": "00000000-0000-0000-0000-000000000000",
                              "schema_id": "Q4zqM7aXqm7gDQkUVLng9h:2:bc-reg:1.0",
                              "cred_def_id": "Q4zqM7aXqm7gDQkUVLng9h:3:CL:18:tag",
                              "cred_rev_id": null,
                              "rev_reg_id": null
                          }
                      },
                      {
                          "interval": null,
                          "cred_info": {
                              "attrs": {
                                  "attr0": "1",
                                  "attr1": "Nice",
                                  "attr2": "Tractor"
                              },
                              "referent": "00000000-0000-0000-0000-111111111111",
                              "schema_id": "Q4zqM7aXqm7gDQkUVLng9h:2:bc-reg:1.0",
                              "cred_def_id": "Q4zqM7aXqm7gDQkUVLng9h:3:CL:18:tag",
                              "cred_rev_id": null,
                              "rev_reg_id": null
                          }
                      }
                  ],
                  "attr1_uuid": [
                      {
                          "interval": null,
                          "cred_info": {
                              "attrs": {
                                  "attr0": "2",
                                  "attr1": "Hello",
                                  "attr2": "World"
                              },
                              "referent": "00000000-0000-0000-0000-000000000000",
                              "schema_id": "Q4zqM7aXqm7gDQkUVLng9h:2:bc-reg:1.0",
                              "cred_def_id": "Q4zqM7aXqm7gDQkUVLng9h:3:CL:18:tag",
                              "cred_rev_id": null,
                              "rev_reg_id": null
                          }
                      },
                      {
                          "interval": null,
                          "cred_info": {
                              "attrs": {
                                  "attr0": "1",
                                  "attr1": "Nice",
                                  "attr2": "Tractor"
                              },
                              "referent": "00000000-0000-0000-0000-111111111111",
                              "schema_id": "Q4zqM7aXqm7gDQkUVLng9h:2:bc-reg:1.0",
                              "cred_def_id": "Q4zqM7aXqm7gDQkUVLng9h:3:CL:18:tag",
                              "cred_rev_id": null,
                              "rev_reg_id": null
                          }
                      }
                  ],
                  "attr2_uuid": [
                      ...
                  ]
              }
          }
  
      :param filt: filter for matching attributes and values; dict (None or empty for no filter, matching all)
          mapping each cred def identifier to dict mapping attributes to values to match; e.g.,
  
      ::
  
          {
              'Q4zqM7aXqm7gDQkUVLng9h:3:CL:18:tag': {
                  'attr0': 1,  # operation stringifies en passant
                  'attr1': 'Nice'
              },
              ...
          }
  
      :param filt_dflt_incl: whether to include (True) all attributes for schema that filter does not identify
          or to exclude (False) all such attributes
      :return: human-legible dict mapping credential identifiers to human-readable credential briefs
          (not proper indy-sdk creds structures) for creds matching input filter
      """
  
      def _add(briefs):
          nonlocal rv, filt
          for brief in briefs:
              cred_info = brief.get('cred_info', {}) or brief  # briefs could be cred-infos or cred-briefs
              if cred_info['referent'] in rv:
                  continue
              cred_cd_id = cred_info['cred_def_id']
              if (not filt) or (filt_dflt_incl and cred_cd_id not in filt):
                  rv[cred_info['referent']] = cred_info
                  continue
              if filt and cred_cd_id in filt:
                  if ({k: str(filt[cred_cd_id][k]) for k in filt[cred_cd_id]}.items() <= cred_info['attrs'].items()):
                      rv[cred_info['referent']] = cred_info
  
      rv = {}
      if filt is None:
          filt = {}
      if isinstance(creds, dict):
          if all(ok_wallet_reft(k) for k in creds):
              _add(creds.values())
          else:
              for uuid2briefs in (creds.get('attrs', {}), creds.get('predicates', {})):
                  for briefs in uuid2briefs.values():
                      _add(briefs)
      else:
          _add(creds)
      return rv