Merge pull request #383 from cmastalli/topic/copyable

Extended copyable visitor

include/eigenpy/copyable.hpp

 //
-// Copyright (c) 2016-2021 CNRS INRIA
+// Copyright (c) 2016-2023 CNRS INRIA
+// Copyright (c) 2023 Heriot-Watt University
 //
 
 #ifndef __eigenpy_utils_copyable_hpp__
@@ -18,10 +19,14 @@ struct CopyableVisitor : public bp::def_visitor<CopyableVisitor<C> > {
   template <class PyClass>
   void visit(PyClass& cl) const {
     cl.def("copy", &copy, bp::arg("self"), "Returns a copy of *this.");
+    cl.def("__copy__", &copy, bp::arg("self"), "Returns a copy of *this.");
+    cl.def("__deepcopy__", &deepcopy, bp::args("self", "memo"),
+           "Returns a deep copy of *this.");
   }
 
  private:
   static C copy(const C& self) { return C(self); }
+  static C deepcopy(const C& self, bp::dict) { return C(self); }
 };
 }  // namespace eigenpy