Update post-processor to add bos (#42)

- Update post-processor to add bos (4d3ac242e1d717fbebaa94154be38077f4e1623b)

tokenizer.json

@@ -2329,11 +2329,70 @@
     ]
   },
   "post_processor": {
+    "type": "Sequence",
+    "processors": [
+      {
         "type": "ByteLevel",
         "add_prefix_space": true,
         "trim_offsets": false,
         "use_regex": true
       },
+      {
+        "type": "TemplateProcessing",
+        "single": [
+          {
+            "SpecialToken": {
+              "id": "<|begin_of_text|>",
+              "type_id": 0
+            }
+          },
+          {
+            "Sequence": {
+              "id": "A",
+              "type_id": 0
+            }
+          }
+        ],
+        "pair": [
+          {
+            "SpecialToken": {
+              "id": "<|begin_of_text|>",
+              "type_id": 0
+            }
+          },
+          {
+            "Sequence": {
+              "id": "A",
+              "type_id": 0
+            }
+          },
+          {
+            "SpecialToken": {
+              "id": "<|begin_of_text|>",
+              "type_id": 1
+            }
+          },
+          {
+            "Sequence": {
+              "id": "B",
+              "type_id": 1
+            }
+          }
+        ],
+        "special_tokens": {
+          "<|begin_of_text|>": {
+            "id": "<|begin_of_text|>",
+            "ids": [
+              128000
+            ],
+            "tokens": [
+              "<|begin_of_text|>"
+            ]
+          }
+        }
+      }
+    ]
+  },
   "decoder": {
     "type": "ByteLevel",
     "add_prefix_space": true,