diff --git a/setup.py b/setup.py
index cc37127..97f10e6 100644
--- a/setup.py
+++ b/setup.py
@@ -22,7 +22,7 @@
                 'ipython>=7.1.0',
                 'pyUSID',
                 'gdown',
-                'mrcfile'
+                'mrcfile',
                 # generic:
                 # Reader specific ones go to extras
                ]