Change more tests to use import_module for the modules that
should cause tests to be skipped. Also rename import_function
to the more descriptive get_attribute and add a docstring.
diff --git a/Lib/test/test_zlib.py b/Lib/test/test_zlib.py
index adb87ff..cbf844f 100644
--- a/Lib/test/test_zlib.py
+++ b/Lib/test/test_zlib.py
@@ -1,9 +1,10 @@
import unittest
from test import test_support
-import zlib
import binascii
import random
+zlib = test_support.import_module('zlib')
+
class ChecksumTestCase(unittest.TestCase):
# checksum test cases