Issue #16316: mimetypes now recognizes the .xz and .txz (.tar.xz) extensions.

Lib/mimetypes.py

@@ -378,12 +378,14 @@ def _default_mime_types():
         '.taz': '.tar.gz',
         '.tz': '.tar.gz',
         '.tbz2': '.tar.bz2',
+        '.txz': '.tar.xz',
         }
 
     encodings_map = {
         '.gz': 'gzip',
         '.Z': 'compress',
         '.bz2': 'bzip2',
+        '.xz': 'xz',
         }
 
     # Before adding new types, make sure they are either registered with IANA,

Lib/test/test_mimetypes.py

@@ -22,6 +22,8 @@ class MimeTypesTestCase(unittest.TestCase):
         eq(self.db.guess_type("foo.tgz"), ("application/x-tar", "gzip"))
         eq(self.db.guess_type("foo.tar.gz"), ("application/x-tar", "gzip"))
         eq(self.db.guess_type("foo.tar.Z"), ("application/x-tar", "compress"))
+        eq(self.db.guess_type("foo.tar.bz2"), ("application/x-tar", "bzip2"))
+        eq(self.db.guess_type("foo.tar.xz"), ("application/x-tar", "xz"))
 
     def test_data_urls(self):
         eq = self.assertEqual

Misc/NEWS

@@ -44,6 +44,8 @@ Core and Builtins
 Library
 -------
 
+- Issue #16316: mimetypes now recognizes the .xz and .txz (.tar.xz) extensions.
+
 - Issue #15902: Fix imp.load_module() accepting None as a file when loading an
   extension module.