message: avoid duplicated user defined structs
diff: @@ -1903,6 +1903,14 @@ PyObject *py_ue_factory_create_new(ue_PyUObject *self, PyObject * args)
  }
  }
  + if (u_class->IsChildOf<UUserDefinedStruct>())
  + {
  + if (FindObject<UUserDefinedStruct>(outer, UTF8_TO_TCHAR(obj_name)))
  + {
  + return PyErr_Format(PyExc_Exception, "a structure with this name already exists in the package");
  + }
  + }
  +
  UObject *u_object = nullptr;
  Py_BEGIN_ALLOW_THREADS;
  