Minor cleanups

gevent/_semaphore.py

 import sys
-from gevent.hub import get_hub, getcurrent, PYPY
+from gevent.hub import get_hub, getcurrent
 from gevent.timeout import Timeout
 
 

greentest/2.7pypy/test_subprocess.py

@@ -195,7 +195,7 @@ class ProcessTestCase(BaseTestCase):
         self.assertEqual(p.returncode, 47)
 
     @unittest.skipIf(sysconfig.is_python_build() or PYPY,
-                     "need an installed Python. See #7774. Also fails to get sys.prefix on PyPy")
+                     "need an installed Python. See #7774. Also fails to get sys.prefix on stock PyPy")
     def test_executable_without_cwd(self):
         # For a normal installation, it should work without 'cwd'
         # argument.  For test runs in the build directory, see #7774.