diff --git a/openquake/hazardlib/calc/filters.py b/openquake/hazardlib/calc/filters.py
index <HASH>..<HASH> 100644
--- a/openquake/hazardlib/calc/filters.py
+++ b/openquake/hazardlib/calc/filters.py
@@ -209,7 +209,7 @@ class SourceFilter(object):
         if sitecol is not None and len(sitecol) < len(sitecol.complete):
             raise ValueError('%s is not complete!' % sitecol)
         self.hdf5path = hdf5path
-        if (hdf5path and
+        if hdf5path and (
                 config.distribution.oq_distribute in ('no', 'processpool') or
                 config.directory.shared_dir):  # store the sitecol
             with hdf5.File(hdf5path, 'w') as h5:
Small fix [skip CI]