code: def _str_index(self):
      idx = self["index"]
      out = []
      default_section = idx.get("default", "")
      out += [f".. index:: {default_section}"]
      for section, references in idx.items():
          if section == "default":
              continue
          out += [f"   :{section}: {references}"]
      return out
  
imports: import inspect
  import textwrap
  import re
  import pydoc
  from warnings import warn
  import collections
  import sys
  from packaging.version import Version
label_desc: Use image node_id 23 for calling the NumpyDocString obj's underlying member method code with example usage: obj._str_index() and returns: out