--- a/tests/test_shasum.py	Fri Apr 29 09:27:05 2022 +0200
+++ b/tests/test_shasum.py	Fri Apr 29 10:19:27 2022 +0200
@@ -9,6 +9,10 @@
 import os
 import sys
 import unittest
+try:
+    from StringIO import StringIO
+except ImportError:
+    StringIO = None
 
 from _test_setup import DATADIR
 
@@ -18,6 +22,13 @@
 PY2 = sys.version_info[0] <= 2
 
 
+def _memfile():
+    if StringIO:
+        return StringIO()
+    else:
+        return io.StringIO()
+
+
 class ChangedDir(object):
 
     """Context manager to temporarily change the directory"""
@@ -39,7 +50,7 @@
 class SignifyTests(unittest.TestCase):
 
     def test_empty(self):
-        destfile = io.StringIO()
+        destfile = _memfile()
         opts = shasum.gen_opts(algorithm="SHA256",
                                dest=destfile,
                                files=[os.path.join(DATADIR, "empty")])
@@ -49,7 +60,7 @@
                 "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855 *"))
 
     def test_empty_mmap(self):
-        destfile = io.StringIO()
+        destfile = _memfile()
         opts = shasum.gen_opts(algorithm="SHA256",
                                dest=destfile,
                                files=[os.path.join(DATADIR, "empty")],
@@ -60,7 +71,7 @@
                 "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855 *"))
 
     def test_empty_no_mmap(self):
-        destfile = io.StringIO()
+        destfile = _memfile()
         opts = shasum.gen_opts(algorithm="SHA256",
                                dest=destfile,
                                files=[os.path.join(DATADIR, "empty")],