diff --git a/python/obitools3/commands/test.pyx b/python/obitools3/commands/test.pyx
index 6a9d05d..ff65539 100644
--- a/python/obitools3/commands/test.pyx
+++ b/python/obitools3/commands/test.pyx
@@ -94,7 +94,7 @@ def test_set_and_get(config, infos):
     col_name = random_column(infos)
     col = infos['view'][col_name]
     element_names = col.elements_names
-    data_type = col.get_data_type()
+    data_type = col.data_type
     if data_type == "OBI_QUAL" :
         print_test(config, "-")
         return
@@ -172,7 +172,7 @@ def random_col_type():
 
 
 def fill_column(config, infos, col) :
-    data_type = col.get_data_type()
+    data_type = col.data_type
     element_names = col.elements_names
     
     if len(element_names) > 1 :
diff --git a/python/obitools3/obidms/_obidms.pxd b/python/obitools3/obidms/_obidms.pxd
index 2fe4986..1e791a2 100644
--- a/python/obitools3/obidms/_obidms.pxd
+++ b/python/obitools3/obidms/_obidms.pxd
@@ -14,12 +14,11 @@ cdef class OBIDMS_column:
     cdef  OBIDMS_column_p*   pointer
     cdef  OBIDMS             dms
     cdef  OBIView            view
-    cdef  str                data_type
+    cdef  str                data_type                  # associated property: data_type
     cdef  str                dms_name
     cdef  index_t            nb_elements_per_line       # associated property: nb_elements_per_line
     cdef  list               elements_names             # associated property: elements_names
         
-    cpdef str     get_data_type(self)
     cpdef index_t get_nb_lines_used(self)
     cpdef str     get_creation_date(self)
     cpdef str     get_comments(self)
diff --git a/python/obitools3/obidms/_obidms.pyx b/python/obitools3/obidms/_obidms.pyx
index 47ba9c2..bd497d3 100644
--- a/python/obitools3/obidms/_obidms.pyx
+++ b/python/obitools3/obidms/_obidms.pyx
@@ -124,9 +124,6 @@ cdef class OBIDMS_column :
         lines_used = (self.pointer)[0].header.lines_used
         for line_nb in range(lines_used):
             yield self.get_line(line_nb)
-             
-    cpdef str get_data_type(self):
-        return self.data_type
     
     cpdef index_t get_nb_lines_used(self):
         return (self.pointer)[0].header.lines_used
@@ -175,6 +172,11 @@ cdef class OBIDMS_column :
     def nb_elements_per_line(self):
         return self.nb_elements_per_line
 
+    # data_type property getter
+    @property
+    def data_type(self):
+        return self.data_type
+
     @staticmethod
     cdef object get_subclass_type(OBIDMS_column_p column_p) :