code: def registered_aliases(self):
      
      target_factories_by_alias = self._target_by_alias.copy()
      target_factories_by_alias.update(self._target_macro_factory_by_alias)
      return BuildFileAliases(
          targets=target_factories_by_alias,
          objects=self._exposed_object_by_alias.copy(),
          context_aware_object_factories=self._exposed_context_aware_object_factory_by_alias.copy()
      )
docs: Return the registered aliases exposed in BUILD files.
  
      These returned aliases aren't so useful for actually parsing BUILD files.
      They are useful for generating things like http://pantsbuild.github.io/build_dictionary.html.
  
      :returns: A new BuildFileAliases instance containing this BuildConfiguration's registered alias
                mappings.
      :rtype: :class:`pants.build_graph.build_file_aliases.BuildFileAliases`