Update README.md

README.md

@@ -5,9 +5,9 @@ dataset_info:
   - name: mention_span
     dtype: string
   - name: left_context_token
-    dtype: string
+    sequence: string
   - name: right_context_token
-    dtype: string
+    sequence: string
   - name: y_str
     sequence: string
   - name: y_type_str