bpo-40275: Use new test.support helper submodules in tests (GH-21449)

diff --git a/Lib/test/test_binascii.py b/Lib/test/test_binascii.py
index 4532795..4d1bf2c 100644
--- a/Lib/test/test_binascii.py
+++ b/Lib/test/test_binascii.py
@@ -4,7 +4,8 @@
 import binascii
 import array
 import re
-from test import support
+from test.support import warnings_helper
+
 
 # Note: "*_hex" functions are aliases for "(un)hexlify"
 b2a_functions = ['b2a_base64', 'b2a_hex', 'b2a_hqx', 'b2a_qp', 'b2a_uu',
@@ -37,7 +38,7 @@
             self.assertTrue(hasattr(getattr(binascii, name), '__call__'))
             self.assertRaises(TypeError, getattr(binascii, name))
 
-    @support.ignore_warnings(category=DeprecationWarning)
+    @warnings_helper.ignore_warnings(category=DeprecationWarning)
     def test_returned_value(self):
         # Limit to the minimum of all limits (b2a_uu)
         MAX_ALL = 45
@@ -181,7 +182,7 @@
         with self.assertRaises(TypeError):
             binascii.b2a_uu(b"", True)
 
-    @support.ignore_warnings(category=DeprecationWarning)
+    @warnings_helper.ignore_warnings(category=DeprecationWarning)
     def test_crc_hqx(self):
         crc = binascii.crc_hqx(self.type2test(b"Test the CRC-32 of"), 0)
         crc = binascii.crc_hqx(self.type2test(b" this string."), crc)
@@ -201,7 +202,7 @@
 
         self.assertRaises(TypeError, binascii.crc32)
 
-    @support.ignore_warnings(category=DeprecationWarning)
+    @warnings_helper.ignore_warnings(category=DeprecationWarning)
     def test_hqx(self):
         # Perform binhex4 style RLE-compression
         # Then calculate the hexbin4 binary-to-ASCII translation
@@ -212,7 +213,7 @@
         res = binascii.rledecode_hqx(b)
         self.assertEqual(res, self.rawdata)
 
-    @support.ignore_warnings(category=DeprecationWarning)
+    @warnings_helper.ignore_warnings(category=DeprecationWarning)
     def test_rle(self):
         # test repetition with a repetition longer than the limit of 255
         data = (b'a' * 100 + b'b' + b'c' * 300)
@@ -359,7 +360,7 @@
         self.assertEqual(b2a_qp(type2test(b'a.\n')), b'a.\n')
         self.assertEqual(b2a_qp(type2test(b'.a')[:-1]), b'=2E')
 
-    @support.ignore_warnings(category=DeprecationWarning)
+    @warnings_helper.ignore_warnings(category=DeprecationWarning)
     def test_empty_string(self):
         # A test for SF bug #1022953.  Make sure SystemError is not raised.
         empty = self.type2test(b'')
@@ -384,7 +385,7 @@
         # crc_hqx needs 2 arguments
         self.assertRaises(TypeError, binascii.crc_hqx, "test", 0)
 
-    @support.ignore_warnings(category=DeprecationWarning)
+    @warnings_helper.ignore_warnings(category=DeprecationWarning)
     def test_unicode_a2b(self):
         # Unicode strings are accepted by a2b_* functions.
         MAX_ALL = 45