bpo-31787: Prevent refleaks when calling __init__() more than once (GH-3995)

(cherry picked from commit d019bc8319ea35e93bf4baa38098ff1b57cd3ee5)

Co-authored-by: Oren Milman <orenmn@gmail.com>
diff --git a/Lib/test/test_lzma.py b/Lib/test/test_lzma.py
index d7a8576..3dc2c1e 100644
--- a/Lib/test/test_lzma.py
+++ b/Lib/test/test_lzma.py
@@ -4,6 +4,8 @@
 import pathlib
 import pickle
 import random
+import sys
+from test import support
 import unittest
 
 from test.support import (
@@ -364,6 +366,15 @@
             with self.assertRaises(TypeError):
                 pickle.dumps(LZMADecompressor(), proto)
 
+    @support.refcount_test
+    def test_refleaks_in_decompressor___init__(self):
+        gettotalrefcount = support.get_attribute(sys, 'gettotalrefcount')
+        lzd = LZMADecompressor()
+        refs_before = gettotalrefcount()
+        for i in range(100):
+            lzd.__init__()
+        self.assertAlmostEqual(gettotalrefcount() - refs_before, 0, delta=10)
+
 
 class CompressDecompressFunctionTestCase(unittest.TestCase):