--- a/cubicweb/server/sources/rql2sql.py	Thu Dec 19 00:59:27 2019 +0100
+++ b/cubicweb/server/sources/rql2sql.py	Thu Dec 19 10:31:49 2019 +0100
@@ -68,6 +68,8 @@
 
 def default_update_cb_stack(self, stack):
     stack.append(self.source_execute)
+
+
 FunctionDescr.update_cb_stack = default_update_cb_stack
 FunctionDescr.source_execute = None
 
@@ -75,6 +77,7 @@
 def length_source_execute(source, session, value):
     return len(value.getvalue())
 
+
 LENGTH = get_func_descr('LENGTH')
 LENGTH.source_execute = length_source_execute