diff --git a/python/obitools3/obidms/_obidms.pxd b/python/obitools3/obidms/_obidms.pxd
index 20c5375..99478d5 100644
--- a/python/obitools3/obidms/_obidms.pxd
+++ b/python/obitools3/obidms/_obidms.pxd
@@ -67,10 +67,6 @@ cdef class OBIView:
     cdef object get_view_subclass(str view_type)
  
 
-cdef class OBIView_NUC_SEQS(OBIView) :
-    pass
-
-
 cdef class OBIView_line :
 
     cdef index_t _index
diff --git a/python/obitools3/obidms/_obidms.pyx b/python/obitools3/obidms/_obidms.pyx
index c35cd14..532c788 100644
--- a/python/obitools3/obidms/_obidms.pyx
+++ b/python/obitools3/obidms/_obidms.pyx
@@ -30,8 +30,6 @@ from ._obidms cimport OBIDMS, \
 
 from ._obitaxo cimport OBI_Taxonomy
 
-from ._obiseq cimport OBI_Nuc_Seq, OBI_Nuc_Seq_Stored
-
 from ._obidmscolumn_int cimport OBIDMS_column_int, \
                                 OBIDMS_column_multi_elts_int
                                 
@@ -132,7 +130,7 @@ cdef class OBIDMS_column :
     def alias(self):
         return self._alias
     @alias.setter
-    def alias(self, new_alias):
+    def alias(self, new_alias):  # @DuplicatedSignature
         self._view.change_column_alias(self._alias, new_alias)
 
     # elements_names property getter
@@ -490,7 +488,7 @@ cdef class OBIView :
 
     # view type property getter
     @property
-    def type(self):
+    def type(self):  # @ReservedAssignment
         return bytes2str(self._pointer.infos.view_type)
 
     # columns property getter
@@ -518,20 +516,6 @@ cdef class OBIView :
 ######################################################################################################
 
 
-cdef class OBIView_NUC_SEQS(OBIView):
-    
-    
-    def __getitem__(self, object item) :
-        if type(item) == str :
-            return (self._columns)[item]
-        elif type(item) == int :
-            return OBI_Nuc_Seq_Stored(self, item)
-    
-    
-    def __setitem__(self, index_t line_idx, OBI_Nuc_Seq sequence_obj) :
-        for key in sequence_obj :
-            self[line_idx][key] = sequence_obj[key]
-
 
 ######################################################################################################
 
@@ -609,9 +593,9 @@ cdef class OBIView_line_selection(list):
     def append(self, index_t idx) :
         if idx >= self._view.line_count :
             raise Exception("Error: trying to select a line beyond the line count of a view")
- #       if idx in self :    # TODO discuss. Discuss order too
- #           pass    
- #       else :
+#       if idx in self :    # TODO discuss. Discuss order too
+#           pass    
+#       else :
         super(OBIView_line_selection, self).append(idx)
 
 
@@ -663,7 +647,7 @@ cdef class OBIDMS :
 
 
     cpdef OBIView clone_view(self, str view_name, object view_to_clone, str comments="") :
-        cdef object view_class
+        cdef object view_class  # @DuplicatedSignature
         cdef str    view_type   
         # Get right subclass depending on view type
         if type(view_to_clone) == str :
@@ -675,7 +659,7 @@ cdef class OBIDMS :
     
     
     cpdef OBIView clone_view_with_line_selection(self, str view_name, OBIView_line_selection line_selection, str comments="") :
-        cdef object view_class
+        cdef object view_class  # @DuplicatedSignature
         # Get right subclass depending on view type
         view_class = OBIView.get_view_subclass(line_selection._view.type)
         return view_class(self, view_name, new=True, view_to_clone=line_selection._view, line_selection=line_selection, comments=comments)
diff --git a/python/obitools3/obidms/_obiview_nuc_seq.pxd b/python/obitools3/obidms/_obiview_nuc_seq.pxd
new file mode 100644
index 0000000..0fa72d3
--- /dev/null
+++ b/python/obitools3/obidms/_obiview_nuc_seq.pxd
@@ -0,0 +1,8 @@
+#cython: language_level=3
+
+from ._obidms cimport OBIView
+from ._obiseq cimport OBI_Nuc_Seq, OBI_Nuc_Seq_Stored
+
+
+cdef class OBIView_NUC_SEQS(OBIView):
+    pass
\ No newline at end of file
diff --git a/python/obitools3/obidms/_obiview_nuc_seq.pyx b/python/obitools3/obidms/_obiview_nuc_seq.pyx
new file mode 100644
index 0000000..141a6ac
--- /dev/null
+++ b/python/obitools3/obidms/_obiview_nuc_seq.pyx
@@ -0,0 +1,19 @@
+#cython: language_level=3
+
+from .capi.obitypes cimport index_t
+
+
+cdef class OBIView_NUC_SEQS(OBIView):
+    
+    
+    def __getitem__(self, object item) :
+        if type(item) == str :
+            return (self._columns)[item]
+        elif type(item) == int :
+            return OBI_Nuc_Seq_Stored(self, item)
+    
+    
+    def __setitem__(self, index_t line_idx, OBI_Nuc_Seq sequence_obj) :
+        for key in sequence_obj :
+            self[line_idx][key] = sequence_obj[key]
+