diff --git a/pilot/conversation.py b/pilot/conversation.py
new file mode 100644
index 000000000..4db5d9548
--- /dev/null
+++ b/pilot/conversation.py
@@ -0,0 +1,151 @@
+#!/usr/bin/env python3
+# -*- coding:utf-8 -*-
+
+import dataclasses
+from enum import auto, Enum
+from typing import List, Tuple, Any
+
+
+class SeparatorStyle(Enum):
+    
+    SINGLE = auto()
+    TWO = auto()
+
+@dataclasses.dataclass
+class Conversation:
+    """This class keeps all conversation history. """
+
+    system: str
+    roles: List[str]
+    messages: List[List[str]] 
+    offset: int
+    sep_style: SeparatorStyle = SeparatorStyle.SINGLE
+    sep: str = "###"
+    sep2: str = None
+
+    # Used for gradio server
+    skip_next: bool = False
+    conv_id: Any = None
+
+    def get_prompt(self):
+        if self.sep_style == SeparatorStyle.SINGLE:
+            ret = self.system
+            for role, message in self.messages:
+                if message:
+                    ret += self.sep + " " + role + ": " + message
+                else:
+                    ret += self.sep + " " + role + ":"
+            return ret
+
+        elif self.sep_style == SeparatorStyle.TWO:
+            seps = [self.sep, self.sep2]
+            ret = self.system + seps[0]
+            for i, (role, message) in enumerate(self.messages):
+                if message:
+                    ret += role + ":" + message + seps[i % 2]
+                else:
+                    ret += role + ":"
+            return ret
+
+        else:
+            raise ValueError(f"Invalid style: {self.sep_style}")
+                
+
+    def append_message(self, role, message):
+        self.messages.append([role, message])
+    
+    def to_gradio_chatbot(self):
+        ret = []
+        for i, (role, msg) in enumerate(self.messages[self.offset :]):
+            if i % 2 == 0:
+                ret.append([msg, None])
+            else:
+                ret[-1][-1] = msg
+
+        return ret
+
+    def copy(self):
+        return Conversation(
+            system=self.system,
+            roles=self.roles,
+            messages=[[x, y] for x, y in self.messages],
+            offset=self.offset,
+            sep_style=self.sep_style,
+            sep=self.sep,
+            sep2=self.sep2,
+            conv_id=self.conv_id,
+        )
+
+    def dict(self):
+        return {
+            "system": self.system,
+            "roles": self.roles,
+            "messages": self.messages,
+            "offset": self.offset,
+            "sep": self.sep,
+            "sep2": self.sep2,
+            "conv_id": self.conv_id
+        }
+
+
+conv_one_shot = Conversation(
+    system="A chat between a curious human and an artificial intelligence assistant, who very familiar with database related knowledge. "
+    "The assistant gives helpful, detailed, professional and polite answers to the human's questions. ",
+    roles=("Human", "Assistant"),
+    messages=(
+        (
+            "Human",
+            "What are the key differences between mysql and postgres?",
+        ),
+        (
+            "Assistant",
+            "MySQL and PostgreSQL are both popular open-source relational database management systems (RDBMS) "
+            "that have many similarities but also some differences. Here are some key differences: \n"
+            "1. Data Types: PostgreSQL has a more extensive set of data types, "
+            "including support for array, hstore, JSON, and XML, whereas MySQL has a more limited set.\n"
+            "2. ACID compliance: Both MySQL and PostgreSQL support ACID compliance (Atomicity, Consistency, Isolation, Durability), "
+            "but PostgreSQL is generally considered to be more strict in enforcing it.\n"
+            "3. Replication: MySQL has a built-in replication feature, which allows you to replicate data across multiple servers,"
+            "whereas PostgreSQL has a similar feature, but it is not as mature as MySQL's.\n"
+            "4. Performance: MySQL is generally considered to be faster and more efficient in handling large datasets, "
+            "whereas PostgreSQL is known for its robustness and reliability.\n"
+            "5. Licensing: MySQL is licensed under the GPL (General Public License), which means that it is free and open-source software, "
+            "whereas PostgreSQL is licensed under the PostgreSQL License, which is also free and open-source but with different terms.\n"
+
+            "Ultimately, the choice between MySQL and PostgreSQL depends on the specific needs and requirements of your application. "
+            "Both are excellent database management systems, and choosing the right one "
+            "for your project requires careful consideration of your application's requirements, performance needs, and scalability."
+        ),
+    ),
+    offset=2,
+    sep_style=SeparatorStyle.SINGLE,
+    sep="###"
+)
+
+conv_vicuna_v1 = Conversation(
+    system = "A chat between a curious user and an artificial intelligence assistant, who very familiar with database related knowledge. "
+    "The assistant gives helpful, detailed, professional and polite answers to the user's questions. ",
+    roles=("USER", "ASSISTANT"),
+    messages=(),
+    offset=0,
+    sep_style=SeparatorStyle.TWO,
+    sep=" ",
+    sep2="</s>",
+)
+
+conv_template = {
+    "conv_one_shot": conv_one_shot,
+    "vicuna_v1": conv_vicuna_v1
+}
+
+
+def get_default_conv_template(model_name: str = "vicuna-13b"):
+    model_name = model_name.lower()
+    if "vicuna" in model_name:
+        return conv_vicuna_v1
+    return conv_one_shot
+
+
+def compute_skip_echo_len(prompt):
+    skip_echo_len = len(prompt) + 1 - prompt.count("</s>") * 3
+    return skip_echo_len
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