replace python django backend with nodejs backend

ai/QwenAi.py

@@ -0,0 +1,38 @@
+import torch
+from AiBase import AiBase
+
+
+class QwenAi(AiBase):
+    default_device = 'cuda'  # the device to load the model onto
+    default_model_id = 'Qwen/Qwen1.5-1.8B-Chat'
+
+    default_instruction = {'role': 'system',
+                           'name': 'system',
+                           'content': 'Your name is "Laura". You are an AI created by Alice.'}
+
+    def __init__(self, model_id_or_path=default_model_id):
+        super().__init__(model_id_or_path)
+
+    def generate(self, messages):
+        try:
+            # prepare
+            messages = [m for m in messages if m['role'] != 'system']
+            input_messages = [self.default_instruction] + messages
+
+            # generate
+            text = self.tokenizer.apply_chat_template(input_messages, tokenize=False, add_generation_prompt=True)
+            model_inputs = self.tokenizer([text], return_tensors='pt').to(self.default_device)
+            generated_ids = self.model.generate(model_inputs.input_ids, max_new_tokens=300)
+            generated_ids = [
+                output_ids[len(input_ids):] for input_ids, output_ids in zip(model_inputs.input_ids, generated_ids)
+            ]
+            response = self.tokenizer.batch_decode(generated_ids, skip_special_tokens=True)[0]
+
+            # add response and save conversation
+            response_entry = {'role': 'assistant', 'name': 'assistant', 'content': response}
+            messages.append(response_entry)
+            self.record_conversation(input_messages, response_entry)
+
+            return messages
+        finally:
+            torch.cuda.empty_cache()  # clear cache or the gpu mem will be used a lot