https://github.com/indygreg/python-zstandard/pull/221

commit e362dd47a0a339cd95a663ca4e54e628060ce6f1
Author: Bernhard M. Wiedemann <bwiedemann@suse.de>
Date:   Fri Apr 5 08:55:10 2024 +0200

    Support zstd-1.5.6

diff --git a/c-ext/backend_c.c b/c-ext/backend_c.c
index bf61f9c..aabe30b 100644
--- a/c-ext/backend_c.c
+++ b/c-ext/backend_c.c
@@ -152,7 +152,7 @@ void zstd_module_init(PyObject *m) {
     PyObject *features = NULL;
     PyObject *feature = NULL;
     unsigned zstd_ver_no = ZSTD_versionNumber();
-    unsigned our_hardcoded_version = 10505;
+    unsigned our_hardcoded_version = 10506;
     if (ZSTD_VERSION_NUMBER != our_hardcoded_version ||
         zstd_ver_no != our_hardcoded_version) {
         PyErr_Format(
diff --git a/tests/test_module_attributes.py b/tests/test_module_attributes.py
index 145f7be..1f37b82 100644
--- a/tests/test_module_attributes.py
+++ b/tests/test_module_attributes.py
@@ -5,7 +5,7 @@ import zstandard as zstd
 
 class TestModuleAttributes(unittest.TestCase):
     def test_version(self):
-        self.assertEqual(zstd.ZSTD_VERSION, (1, 5, 5))
+        self.assertEqual(zstd.ZSTD_VERSION, (1, 5, 6))
 
         self.assertEqual(zstd.__version__, "0.22.0")