diff --git a/Lib/test/test_mmap.py b/Lib/test/test_mmap.py
@@ -1,11 +1,15 @@
-from test.support import (requires, _2G, _4G, gc_collect, cpython_only)
from test.support.import_helper import import_module
from test.support.os_helper import TESTFN, unlink
import unittest
import os
import re
import itertools
import socket
import sys
import weakref

@@ -14,6 +18,16 @@

PAGESIZE = mmap.PAGESIZE


class MmapTests(unittest.TestCase):

@@ -609,21 +623,23 @@ def test_tagname(self):
        data1 = b"0123456789"
        data2 = b"abcdefghij"
        assert len(data1) == len(data2)

        # Test same tag
-        m1 = mmap.mmap(-1, len(data1), tagname="foo")
        m1[:] = data1
-        m2 = mmap.mmap(-1, len(data2), tagname="foo")
        m2[:] = data2
        self.assertEqual(m1[:], data2)
        self.assertEqual(m2[:], data2)
        m2.close()
        m1.close()

        # Test different tag
-        m1 = mmap.mmap(-1, len(data1), tagname="foo")
        m1[:] = data1
-        m2 = mmap.mmap(-1, len(data2), tagname="boo")
        m2[:] = data2
        self.assertEqual(m1[:], data1)
        self.assertEqual(m2[:], data2)
@@ -634,17 +650,18 @@ def test_tagname(self):
    @unittest.skipUnless(os.name == 'nt', 'requires Windows')
    def test_sizeof(self):
        m1 = mmap.mmap(-1, 100)
-        tagname = "foo"
        m2 = mmap.mmap(-1, 100, tagname=tagname)
        self.assertEqual(sys.getsizeof(m2),
                         sys.getsizeof(m1) + len(tagname) + 1)

    @unittest.skipUnless(os.name == 'nt', 'requires Windows')
    def test_crasher_on_windows(self):
        # Should not crash (Issue 1733986)
-        m = mmap.mmap(-1, 1000, tagname="foo")
        try:
-            mmap.mmap(-1, 5000, tagname="foo")[:] # same tagname, but larger size
        except:
            pass
        m.close()
@@ -707,7 +724,6 @@ def test_write_returning_the_number_of_bytes_written(self):
        self.assertEqual(mm.write(b"yz"), 2)
        self.assertEqual(mm.write(b"python"), 6)

-    @unittest.skipIf(os.name == 'nt', 'cannot resize anonymous mmaps on Windows')
    def test_resize_past_pos(self):
        m = mmap.mmap(-1, 8192)
        self.addCleanup(m.close)
@@ -797,6 +813,80 @@ def test_madvise(self):
        self.assertEqual(m.madvise(mmap.MADV_NORMAL, 0, 2), None)
        self.assertEqual(m.madvise(mmap.MADV_NORMAL, 0, size), None)


class LargeMmapTests(unittest.TestCase):