diff --git a/sumpy/expansion/multipole.py b/sumpy/expansion/multipole.py
index 3d67fde839346b0af27ac7463b9c71d4028c1e9e..a5ac8e145493892bc9b51d787d558ebed28ba7f7 100644
--- a/sumpy/expansion/multipole.py
+++ b/sumpy/expansion/multipole.py
@@ -91,11 +91,10 @@ class VolumeTaylorMultipoleExpansionBase(MultipoleExpansionBase):
             rscale = 1
 
         base_taker = kernel.get_derivative_taker(bvec, rscale, sac)
-        # Following is a no-op, but reduces the cases we have to handle
-        # in AxisTargetDerivative.postprocess_at_target and
-        # DirectionalTargetDerivative.postprocess_at_target because
-        # the type will always be DifferentiatedExprDerivativeTaker
-        # that we are passing to postprocess_at_target
+        # Following is a no-op, but AxisTargetDerivative.postprocess_at_target and
+        # DirectionalTargetDerivative.postprocess_at_target only handles
+        # DifferentiatedExprDerivativeTaker and sympy expression, so we need to
+        # make the taker a DifferentitatedExprDerivativeTaker instance.
         base_taker = DifferentiatedExprDerivativeTaker(base_taker,
                 {tuple([0]*self.dim): 1})
         taker = kernel.postprocess_at_target(base_taker, bvec)