'Writing my own WebSocket using the python socket server module

I wanted to know how WebSocket servers are written so I tried making my own. I used this as my reference and wrote a simple ThreadedTCPServer from the socket server module this is my code for it

import base64
import hashlib
import re
import socketserver


def make_headers(headers: dict):
    result = ""
    result += "HTTP/1.1 101 Switching Protocols\r\n"
    for header, value in headers.items():
        result += f"{header}: {value}\r\n"
    return result


def get_key(handshake_string):
    key = re.findall(r"Sec-WebSocket-Key: .*", handshake_string)[0]
    key = key.split(":")[1].strip()
    return key


class Handler(socketserver.BaseRequestHandler):
    MAGIC = "258EAFA5-E914-47DA-95CA-C5AB0DC85B11"

    def setup(self) -> None:
        handshake_text = self.request.recv(1024).decode('utf-8')
        print(handshake_text)
        key = get_key(handshake_text)
        key = key + self.MAGIC
        print(key)
        key = hashlib.sha1(key.encode()).digest()
        key = base64.b64encode(key).decode()
        print(key)

        headers = {"Upgrade": "websocket", "Connection": "Upgrade",
                   "Sec-WebSocket-Accept": key}

        headers = make_headers(headers)
        self.request.send(headers.encode())

    def handle(self) -> None:
        self.request.send(b"Connection Finally works ^_^")
        print("conn sent?")

    def finish(self) -> None:
        print("Connection Over :(")


if __name__ == '__main__':
    server = socketserver.ThreadingTCPServer(("127.0.0.1", 2449), Handler)
    server.serve_forever()

As mentioned in the referenced site, I have implemented the handshake in the setup method of my handler class however when I open my simple HTML document for testing the server I don't get my desired result in the browser console (blank) this is my html code:

<!doctype html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport"
          content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Socket test</title>
</head>
<body>
<h1>Sample text1</h1>
<script>
    var ws = new WebSocket("ws://127.0.0.1:2449/")
    ws.onopen = function() {
        console.log("Connection Established!")
    }

    ws.onmessage = function(msg)
    {
        console.log("message received!")
        console.log(msg)
    }

    ws.onerror = function(err){
        console.log(err)
    }
</script>
</body>
</html>

The html page sends a socket request which triggers the server handler and upon the handshake the request closes. is there any reason as to why this happens?

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'Writing my own WebSocket using the python socket server module

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