code: def get_url(path, repo=None, rev=None, remote=None):
      """
      Returns the URL to the storage location of a data file or directory tracked
      in a DVC repo. For Git repos, HEAD is used unless a rev argument is
      supplied. The default remote is tried unless a remote argument is supplied.
  
      Raises OutputNotFoundError if the file is not tracked by DVC.
  
      NOTE: This function does not check for the actual existence of the file or
      directory in the remote storage.
      """
      from dvc.config import NoRemoteError
      from dvc_data.index import StorageKeyError
  
      repo_kwargs: Dict[str, Any] = {}
      if remote:
          repo_kwargs["config"] = {"core": {"remote": remote}}
      with Repo.open(
          repo,
          rev=rev,
          subrepos=True,
          uninitialized=True,
          **repo_kwargs,
      ) as _repo:
          index, entry = _repo.get_data_index_entry(path)
          with reraise(
              (StorageKeyError, ValueError),
              NoRemoteError(f"no remote specified in {_repo}"),
          ):
              remote_fs, remote_path = index.storage_map.get_remote(
                  entry
              )
              return remote_fs.unstrip_protocol(remote_path)
  
file_path: dvc/dvc/api/data.py
imports: from contextlib import _GeneratorContextManager
  from contextlib import contextmanager
  from typing import Any, Dict, Optional
  from funcy import reraise
  from dvc.exceptions import FileMissingError, OutputNotFoundError, PathMissingError
  from dvc.repo import Repo
label_desc: Use image node_id 2 for calling a global function with example usage: get_url(path, repo, rev, remote) and returns: remote_fs