Re-use tarfile_open for Python 2.6 compatibilty.

setuptools/tests/test_easy_install.py

@@ -364,7 +364,7 @@ class TestSetupRequires:
                 # extracted path to sys.path so foo.bar v0.1 is importable
                 foobar_1_dir = os.path.join(temp_dir, 'foo.bar-0.1')
                 os.mkdir(foobar_1_dir)
-                with tarfile.open(foobar_1_archive) as tf:
+                with tarfile_open(foobar_1_archive) as tf:
                     tf.extractall(foobar_1_dir)
                 sys.path.insert(1, foobar_1_dir)
 
@@ -462,17 +462,13 @@ def make_sdist(dist_path, files):
     listed in ``files`` as ``(filename, content)`` tuples.
     """
 
-    dist = tarfile.open(dist_path, 'w:gz')
-
-    try:
+    with tarfile_open(dist_path, 'w:gz') as dist:
         for filename, content in files:
             file_bytes = io.BytesIO(content.encode('utf-8'))
             file_info = tarfile.TarInfo(name=filename)
             file_info.size = len(file_bytes.getvalue())
             file_info.mtime = int(time.time())
             dist.addfile(file_info, fileobj=file_bytes)
-    finally:
-        dist.close()
 
 
 def create_setup_requires_package(path, distname='foobar', version='0.1',