diff --git a/sand/controllers/table.py b/sand/controllers/table.py
index 4010e89..7bb624d 100644
--- a/sand/controllers/table.py
+++ b/sand/controllers/table.py
@@ -18,7 +18,7 @@
 import sm.outputs.semantic_model as O
 from flask import jsonify, request, make_response
 from peewee import DoesNotExist, fn
-
+from drepr.engine import OutputFormat
 from werkzeug.exceptions import BadRequest, NotFound
 
 
@@ -121,7 +121,7 @@ def export_table_data(id: int):
     rows: List[TableRow] = list(TableRow.select().where(TableRow.table == table))
 
     # export the data using drepr library
-    content = DreprExport().export_data(table, rows, sm.data, 'TTL')
+    content = DreprExport().export_data(table, rows, sm.data, OutputFormat.TTL)
     resp = make_response(content)
     resp.headers["Content-Type"] = "text/ttl; charset=utf-8"
     if request.args.get("attachment", "false") == "true":
diff --git a/sand/extension_interface/export.py b/sand/extension_interface/export.py
index 98f573d..5b7e864 100644
--- a/sand/extension_interface/export.py
+++ b/sand/extension_interface/export.py
@@ -1,10 +1,10 @@
 from abc import ABC, abstractmethod
-from typing import List, AnyStr
+from typing import List
 
 import sm.outputs.semantic_model as O
 from sand.models.table import Table, TableRow
-from sand.models.table import Table, TableRow
 from drepr.models import DRepr
+from drepr.engine import OutputFormat
 
 
 class IExport(ABC):
@@ -20,6 +20,6 @@ def export_data_model(self, table: Table, sm: O.SemanticModel) -> DRepr:
 
     @abstractmethod
     def export_data(self, table: Table, rows: List[TableRow], sm: O.SemanticModel,
-                    output_format: AnyStr):
+                    output_format: OutputFormat):
         """Search Class using name"""
         pass
diff --git a/sand/extensions/export/drepr/main.py b/sand/extensions/export/drepr/main.py
index 02aa286..30768ef 100644
--- a/sand/extensions/export/drepr/main.py
+++ b/sand/extensions/export/drepr/main.py
@@ -1,4 +1,5 @@
-from typing import List, Set, AnyStr
+from typing import List, Set
+from enum import Enum
 from sand.config import SETTINGS
 from sand.models.ontology import OntProperty, OntPropertyAR, OntPropertyDataType
 from sand.models.table import Table, TableRow
@@ -127,7 +128,7 @@ def export_data_model(self, table: Table, sm: O.SemanticModel) -> DRepr:
         )
 
     def export_data(self, table: Table, rows: List[TableRow], sm: O.SemanticModel,
-                    output_format: AnyStr):
+                    output_format: OutputFormat):
         """Convert a relational table into RDF format"""
         if len(table.columns) == 0:
             # no column, no data
@@ -142,7 +143,7 @@ def export_data(self, table: Table, rows: List[TableRow], sm: O.SemanticModel,
         content = execute(
             ds_model=self.export_data_model(table, sm),
             resources=resources,
-            output=MemoryOutput(OutputFormat.__getitem__(output_format)),
+            output=MemoryOutput(output_format),
             debug=False,
         )
         return content