code: def _str_index(self):
      idx = self["index"]
      out = []
      if len(idx) == 0:
          return out
  
      out += [".. index:: %s" % idx.get("default", "")]
      for section, references in list(idx.items()):
          if section == "default":
              continue
          elif section == "refguide":
              out += ["   single: %s" % (", ".join(references))]
          else:
              out += ["   %s: %s" % (section, ",".join(references))]
      return out
  
imports: import sys, re, inspect, textwrap, pydoc
  import sphinx
  import collections
  from .docscrape import NumpyDocString, FunctionDoc, ClassDoc
label_desc: Use image node_id 16 for calling the SphinxDocString obj's underlying member method code with example usage: obj._str_index() and returns: out, out