code: def _command_summary():
      # Import here to avoid polluting the datalad.api namespace.
      from collections import defaultdict
      from datalad.interface.base import alter_interface_docs_for_api
      from datalad.interface.base import get_api_name
      from datalad.interface.base import get_cmd_doc
      from datalad.interface.base import get_cmd_summaries
      from datalad.interface.base import get_interface_groups
      from datalad.interface.base import load_interface
  
      groups = get_interface_groups()
      grp_short_descriptions = defaultdict(list)
      for group, _, specs in sorted(groups, key=lambda x: x[1]):
          for spec in specs:
              intf = load_interface(spec)
              if intf is None:
                  continue
              sdescr = (
                  getattr(intf, "short_description", None)
                  or alter_interface_docs_for_api(
                      get_cmd_doc(intf)
                  ).split("\n")[0]
              )
              grp_short_descriptions[group].append(
                  (get_api_name(spec), sdescr)
              )
      return "\n".join(
          get_cmd_summaries(grp_short_descriptions, groups)
      )
  
label_desc: Use image node_id 1 for calling a global function with example usage: _command_summary() and returns: str