add missing python export in bondhandle

modules/mol/base/pymod/export_bond.cc

@@ -52,6 +52,7 @@ void export_Bond()
     .def("GetBondOrder",&BondHandle::GetBondOrder)
     .def("SetBondOrder",&BondHandle::SetBondOrder)
     .def("IsValid", &BondHandle::IsValid)       
+    .def("GetHashCode", &BondHandle::GetHashCode)
     .def(self == self)
     .def(self != self)
     .def(self_ns::str(self))