[2.0.x] Removed usage of deprecated sphinx APIs.

Backport of cc4bb110d3 from master

docs/_ext/djangodocs.py

@@ -10,6 +10,7 @@ from docutils.parsers.rst import Directive, directives
 from sphinx import addnodes
 from sphinx.builders.html import StandaloneHTMLBuilder
 from sphinx.domains.std import Cmdoption
+from sphinx.util import logging
 from sphinx.util.console import bold
 from sphinx.util.nodes import set_source_info
 
@@ -18,6 +19,7 @@ try:
 except ImportError:  # Sphinx 1.6+
     from sphinx.writers.html import HTMLTranslator
 
+logger = logging.getLogger(__name__)
 # RE for option descriptions without a '--' prefix
 simple_option_desc_re = re.compile(
     r'([-_a-zA-Z0-9]+)(\s*.*?)(?=,\s+(?:/|-|--)|$)')
@@ -44,7 +46,7 @@ def setup(app):
         rolename="lookup",
         indextemplate="pair: %s; field lookup type",
     )
-    app.add_description_unit(
+    app.add_object_type(
         directivename="django-admin",
         rolename="djadmin",
         indextemplate="pair: %s; django-admin command",
@@ -310,7 +312,7 @@ class DjangoStandaloneHTMLBuilder(StandaloneHTMLBuilder):
 
     def finish(self):
         super().finish()
-        self.info(bold("writing templatebuiltins.js..."))
+        logger.info(bold("writing templatebuiltins.js..."))
         xrefs = self.env.domaindata["std"]["objects"]
         templatebuiltins = {
             "ttags": [