File avoid_contextlib2.patch of Package python-sphinxcontrib-trio

--- a/sphinxcontrib_trio/__init__.py
+++ b/sphinxcontrib_trio/__init__.py
@@ -92,13 +92,6 @@ CM_CODES = set()
 from contextlib import contextmanager
 CM_CODES.add(contextmanager(None).__code__)
 
-try:
-    from contextlib2 import contextmanager as contextmanager2
-except ImportError:
-    pass
-else:
-    CM_CODES.add(contextmanager2(None).__code__)
-
 extended_function_option_spec = {
     "async": directives.flag,
     "decorator": directives.flag,
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -1,6 +1,5 @@
 pytest
 pytest-cov
 async_generator
-contextlib2
 lxml
 cssselect
--- a/tests/test_sphinxcontrib_trio.py
+++ b/tests/test_sphinxcontrib_trio.py
@@ -14,13 +14,6 @@ from pathlib import Path
 import lxml.html
 
 try:
-    from contextlib2 import contextmanager as contextmanager2
-except ImportError:
-    have_contextmanager2 = False
-else:
-    have_contextmanager2 = True
-
-try:
     from async_generator import async_generator, yield_
 except ImportError:
     have_async_generator = False
@@ -108,12 +101,6 @@ def test_sniff_options():
 
     check(cm, "with")
 
-    if have_contextmanager2:
-        @contextmanager2
-        def cm2():  # pragma: no cover
-            yield
-        check(cm2, "with")
-
     def manual_cm():  # pragma: no cover
         pass
     manual_cm.__returns_contextmanager__ = True
--- a/docs/source/index.rst
+++ b/docs/source/index.rst
@@ -111,9 +111,7 @@ Autodetection heuristics
 * ``:with:`` is autodetected for:
 
   * functions decorated with `contextlib.contextmanager
-    <https://docs.python.org/3/library/contextlib.html#contextlib.contextmanager>`__
-    or `contextlib2.contextmanager
-    <https://contextlib2.readthedocs.io/en/stable/#contextlib2.contextmanager>`__,
+    <https://docs.python.org/3/library/contextlib.html#contextlib.contextmanager>`__,
 
   * functions that have an attribute ``__returns_contextmanager__``
     with a truthy value.