bpo-44439: BZ2File.write() / LZMAFile.write() handle buffer protocol correctly (GH-26764) (GH-26845)

No longer use len() to get the length of the input data. For some buffer protocol objects,
the length obtained by using len() is wrong.
(cherry picked from commit bc6c12c72a9536acc96e7b9355fd69d1083a43c1)

Co-authored-by: Ma Lin <animalize@users.noreply.github.com>
diff --git a/Lib/test/test_lzma.py b/Lib/test/test_lzma.py
index db20300..1e2066b 100644
--- a/Lib/test/test_lzma.py
+++ b/Lib/test/test_lzma.py
@@ -1,4 +1,5 @@
 import _compression
+import array
 from io import BytesIO, UnsupportedOperation, DEFAULT_BUFFER_SIZE
 import os
 import pathlib
@@ -1231,6 +1232,14 @@ def test_issue21872(self):
         self.assertTrue(d2.eof)
         self.assertEqual(out1 + out2, entire)
 
+    def test_issue44439(self):
+        q = array.array('Q', [1, 2, 3, 4, 5])
+        LENGTH = len(q) * q.itemsize
+
+        with LZMAFile(BytesIO(), 'w') as f:
+            self.assertEqual(f.write(q), LENGTH)
+            self.assertEqual(f.tell(), LENGTH)
+
 
 class OpenTestCase(unittest.TestCase):