Grep for 2.7 and remove places for Python 2 support.

Additionally removed also a bit of Zope 2.7 support code.

docs/INSTALL.rst

@@ -16,8 +16,7 @@ available:
 - A supported version of Python, including the development support if
   installed from system-level packages.  Supported versions include:
 
-  * 2.7
-  * 3.5 - 3.8
+  * 3.5 up to 3.8
 
 - Zope needs the Python ``zlib`` module to be importable.  If you are
   building your own Python from source, please be sure that you have the
@@ -72,11 +71,6 @@ Built-in standard buildout configuration
   $ bin/pip install -U pip zc.buildout
   $ bin/buildout
 
-.. note::
-
-  When using Python 2.7 instead of calling ``python3.7 -m venv .`` you have to
-  install `virtualenv` and then call ``python2.7 -m virtualenv .``.
-
 
 Custom buildout configurations
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
@@ -175,11 +169,6 @@ version you find on https://zopefoundation.github.io/Zope/:
   $ bin/pip install Zope==4.1 \
     -c https://zopefoundation.github.io/Zope/releases/4.1/constraints.txt
 
-.. note::
-
-  When using Python 2.7 instead of calling ``python3.7 -m venv zope`` you have
-  to install `virtualenv` and then call ``python2.7 -m virtualenv zope``.
-
 You can also install Zope using a single requirements file. Note that this
 installation method might install packages that are not actually needed (i. e.
 more than are listed in the ``install_requires`` section of ``setup.py``):

docs/operation.rst

@@ -401,7 +401,7 @@ done.
 Troubleshooting
 ---------------
 
-- This version of Zope requires Python 2.7 or Python 3.5 and later.
+- This version of Zope requires Python 3.5 and later.
   It will *not* run with any version of PyPy.
 
 - To build Python extensions you need to have Python configuration

docs/zope4/news.rst

@@ -29,15 +29,14 @@ found in this release.
 
 Extended Python version support
 -------------------------------
-Zope 4 supports Python 2.7 and Python 3.5 up to Python 3.8.
+Zope 5 supports Python 3.5 up to Python 3.8.
 
 The Python 3 support currently covers the core dependencies shipped
-with Zope and is limited to the new WSGI based publisher. The new
-external ZServer project is currently limited to Python 2.7 compatibility
-and likely to stay that way.
+with Zope and is limited to the new WSGI based publisher.
 
-Migrating an existing ZODB to Python 3 is not an automated process. Please
-consult :ref:`zope4zodbmigration` for details.
+Migrating an existing ZODB to Python 3 is not an automated process. You have
+to update to Zope 4 first, see
+`Zope 4 migration <https://zope.readthedocs.io/en/4.x/zope4/migration/index.html>`_.
 
 
 WSGI as the new default server type

src/Testing/ZopeTestCase/testZODBCompat.py

@@ -139,23 +139,13 @@ def afterClear(self):
             os.rmdir(self.import_dir)
         except OSError:
             pass
-        try:
-            import App.config
-        except ImportError:
-            # Restore builtins
-            builtins = getattr(__builtins__, '__dict__', __builtins__)
-            if hasattr(self, '_ih'):
-                builtins['INSTANCE_HOME'] = self._ih
-            if hasattr(self, '_ch'):
-                builtins['CLIENT_HOME'] = self._ch
-        else:
-            # Zope >= 2.7
-            config = App.config.getConfiguration()
-            if hasattr(self, '_ih'):
-                config.instancehome = self._ih
-            if hasattr(self, '_ch'):
-                config.clienthome = self._ch
-            App.config.setConfiguration(config)
+        import App.config
+        config = App.config.getConfiguration()
+        if hasattr(self, '_ih'):
+            config.instancehome = self._ih
+        if hasattr(self, '_ch'):
+            config.clienthome = self._ch
+        App.config.setConfiguration(config)
 
 
 class TestAttributesOfCleanObjects(ZopeTestCase.ZopeTestCase):