code: def run(self):
      import os
      from os.path import relpath
  
      diff_result = self.repo.params.diff(
          a_rev=self.args.a_rev,
          b_rev=self.args.b_rev,
          targets=self.args.targets,
          all=self.args.all,
          deps_only=self.args.deps,
      )
  
      errored = [
          rev
          for rev, err in diff_result.get("errors", {}).items()
          if err
      ]
      if errored:
          ui.error_write(
              "DVC failed to load some metrics for following revisions:"
              f" '{', '.join(errored)}'."
          )
  
      start = relpath(os.getcwd(), self.repo.root_dir)
      diff = diff_result.get("diff", {})
      diff = {
          relpath(path, start): result for path, result in diff.items()
      }
  
      if self.args.json:
          ui.write_json(diff)
      else:
          from dvc.compare import show_diff
  
          show_diff(
              diff,
              title="Param",
              markdown=self.args.markdown,
              no_path=self.args.no_path,
              show_changes=False,
              a_rev=self.args.a_rev,
              b_rev=self.args.b_rev,
          )
  
      return 0
  
file_path: dvc/dvc/commands/params.py
imports: from dvc.cli import completion, formatter
  from dvc.cli.command import CmdBase
  from dvc.cli.utils import append_doc_link
  from dvc.log import logger
  from dvc.ui import ui
label_desc: Use image node_id 1 for calling the CmdParamsDiff obj's underlying member method code with example usage: obj.run() and returns: int