diff --git a/test/unit/test_taxon_filter.py b/test/unit/test_taxon_filter.py
index 1d64ff3c..83fc52a3 100644
--- a/test/unit/test_taxon_filter.py
+++ b/test/unit/test_taxon_filter.py
@@ -365,7 +365,7 @@ def setUp(self):
 
         # tar one db, but not the other
         tar_db_tgz = util.file.mkstempfname('-humanChr9Subset.blastn.db.tar.gz')
-        cmd = ['tar', '-C', self.tempDir, '-cvzf', tar_db_tgz] + map(os.path.basename, glob.glob(os.path.join(self.tempDir, "humanChr9Subset.n*")))
+        cmd = ['tar', '-C', self.tempDir, '-cvzf', tar_db_tgz] + list(os.path.basename(f) for f in glob.glob(os.path.join(self.tempDir, "humanChr9Subset.n*")))
         subprocess.check_call(cmd)
         self.blastdbs_multi[1] = tar_db_tgz
         for idx in glob.glob(os.path.join(self.tempDir, "humanChr9Subset.n*")):