class_docstr: The sole purpose of this domain is a parallel_read_safe data store for the
  redirects mapping.
code: def merge_domaindata(self, docnames, otherdata):
      for src, dst in otherdata["redirects"].items():
          if src not in self.redirects:
              self.redirects[src] = dst
          elif self.redirects[src] != dst:
              raise ValueError(
                  f"Inconsistent redirections from {src} to "
                  f"{self.redirects[src]} and {otherdata['redirects'][src]}"
              )
  
file_path: matplotlib/doc/sphinxext/redirect_from.py
imports: from pathlib import Path
  from docutils.parsers.rst import Directive
  from sphinx.domains import Domain
  from sphinx.util import logging
label_desc: Use image node_id 3 for calling the RedirectFromDomain obj's underlying member method code with example usage: obj.merge_domaindata(docnames, otherdata) without return types