code: def _register_urls(repo, key, urls_by_sr, src_srinfo):
      """Register URLs for a key in a repo based on special remote info
  
      Parameters
      ----------
      repo : AnnexRepo
      key : str
      urls_by_sr : dict
      src_srinfo : dict
  
      Returns
      -------
      list
        IDs of (newly initialized) special remotes in the target dataset that
        can provide the key.
      """
      avail_sr = []
      for src_rid, urls in urls_by_sr.items():
          if not (
              src_rid == "00000000-0000-0000-0000-000000000001"
              or src_srinfo.get(src_rid, {}).get("externaltype", None)
              == "datalad"
          ):
              # TODO generalize to any special remote
              lgr.warning(
                  "Ignore URL for presently unsupported special remote"
              )
              continue
          if (
              src_rid != "00000000-0000-0000-0000-000000000001"
              and src_srinfo[src_rid]
              not in repo.get_special_remotes_wo_timestamp().values()
          ):
              # this is a special remote that the destination repo doesn't know
              sri = src_srinfo[src_rid]
              lgr.debug(
                  "Init additionally required special remote: %s", sri
              )
              repo.init_remote(
                  # TODO what about a naming conflict across all dataset sources?
                  sri["name"],
                  [
                      "{}={}".format(k, v)
                      for k, v in sri.items()
                      if k != "name"
                  ],
              )
              # must update special remote info for later matching
              repo.get_special_remotes_wo_timestamp.cache_clear()
          for url in urls:
              lgr.debug("Register URL for key %s: %s", key, url)
              # TODO OPT: add .register_url(key, batched=False) to AnnexRepo
              #  to speed up this step by batching.
              repo.call_annex(["registerurl", key, url])
          dest_rid = (
              src_rid
              if src_rid == "00000000-0000-0000-0000-000000000001"
              else [
                  k
                  for k, v in repo.get_special_remotes_wo_timestamp().items()
                  if v["name"] == src_srinfo[src_rid]["name"]
              ].pop()
          )
          lgr.debug(
              "Mark key %s as present for special remote: %s",
              key,
              dest_rid,
          )
          repo.call_annex(["setpresentkey", key, dest_rid, "1"])
          # record ID of special remote in dest dataset
          avail_sr.append(dest_rid)
      return avail_sr
  
imports: import logging
  import os.path
  from shutil import copyfile
  import sys
  from datalad.interface.base import Interface
  from datalad.interface.base import build_doc, eval_results
  from datalad.support.constraints import EnsureStr, EnsureNone
  from datalad.interface.common_opts import save_message_opt
  from datalad.support.param import Parameter
  from datalad.distribution.dataset import Dataset, require_dataset
  from datalad.support.annexrepo import AnnexRepo
  from datalad.support.exceptions import CapturedException
  from datalad.utils import ensure_list, get_dataset_root, Path
  from datalad.distribution.dataset import EnsureDataset, datasetmethod, resolve_path
  from functools import lru_cache
label_desc: Use image node_id 4 for calling a global function with example usage: _register_urls(repo, key, urls_by_sr, src_srinfo) and returns: avail_sr