diff --git a/mistral/arch_pybindings.cc b/mistral/arch_pybindings.cc
index d93b7e28..23716c93 100644
--- a/mistral/arch_pybindings.cc
+++ b/mistral/arch_pybindings.cc
@@ -61,8 +61,8 @@ void arch_wrap_python(py::module &m)
 
     typedef const std::vector<BelId> &BelRange;
 
-    typedef const UpDownhillPipRange UphillPipRange;
-    typedef const UpDownhillPipRange DownhillPipRange;
+    typedef UpDownhillPipRange UphillPipRange;
+    typedef UpDownhillPipRange DownhillPipRange;
 
     typedef AllWireRange WireRange;
     typedef const std::vector<BelPin> &BelPinRange;