create_kernel now also takes an assignment collection

kernelcreation.py

@@ -55,6 +55,8 @@ def create_kernel(assignments, target='cpu', data_type="double", iteration_slice
                [0., 4., 4., 4., 0.],
                [0., 0., 0., 0., 0.]])
     """
+    if isinstance(assignments, AssignmentCollection):
+        assignments = assignments.all_assignments
 
     # ----  Normalizing parameters
     split_groups = ()