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Can I make a client socket only to establish a connection using python 3.6

I'm reading about socket module in a web learning site about python, they gave us a simple steps to use socket module like follows:
import socket
with socket.socket() as client_socket:
hostname = '127.0.0.1'
port = 9090
address = (hostname, port)
client_socket.connect(address)
data = 'Wake up, Neo'
data = data.encode()
client_socket.send(data)
response = client_socket.recv(1024)
response = response.decode()
print(response)
when executing I got the error message:
ConnectionRefusedError: [WinError 10061] No connection could be made because the target machine actively refused it.
when I searched about this some sites was talking about server listening and I see in most of tutorials about server socket and they use it along with client one.
so Is the error message related to the fact that I'm not using a server socket and is it a must to use them both
Update:
after reading the answers I got, I went to the test.py file that the course instructors use to evaluate our codes and I see that they make the server socket in it , so the server is already made by them. that take me back to the Error I got why does it happen then.
def server(self):
'''function - creating a server and answering clients'''
self.sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
self.sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
self.sock.bind(('localhost', 9090))
self.ready = True
try:
self.sock.listen(1)
conn, addr = self.sock.accept()
self.connected = True
conn.settimeout(15)
while True:
data = conn.recv(1024)
self.message.append(data.decode('utf8'))
if len(self.message) > 1_000_000:
conn.send(
json.dumps({
'result': 'Too many attempts to connect!'
}).encode('utf8'))
break
if not data:
break

Each connection requires a client, which initiates the connection, and a server, which listens for the incoming connection from the client. The code you have shown is for the client end of the connection. In order for this to run successfully you will need a server listening for the connection you are trying to create.
In the code you showed us you have the lines
hostname = '127.0.0.1'
port = 9090
address = (hostname, port)
client_socket.connect(address)
These are the lines that define what server you are connecting to. In this case it is a server at 127.0.0.1 (which is localhost, the same machine you are running the code on) listening on port 9090.
If you want to make your own server then you can look at the documentation for Python sockets and the particular functions you want to know about are bind, listen, and accept. You can find examples at the bottom of that same page.
Given that you appear to have found this code as part of a course, I suspect they may provide you with matching server code at some point in order to be able to use this example.

Socket programming + HTTP1.1 in Python

The task is building two files client.py and server.py. I am able to connect the client to the server. The problem I encounter is when I trying to send a get request like client.send("bGET /suc.txt HTTP/1.1\r\nHost:127.0.0.1\r\n\r\n"), I do not how to return the file suc.txt to the client from the server side. The scene is a client request file from a server and what the server returns is the respond header and the requested file.
What I wrote so far :
Client:
import socket
target_host = "127.0.0.1"
target_port = 5050
client = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
client.connect((target_host,target_port))
client.send("bGET /suc.txt HTTP/1.1\r\nHost:127.0.0.1\r\n\r\n")
response = client.recv(1024)
print(response.decode())
Server:
import socket
import threading
import urllib.request
HEADER = 64
PORT = 5050
HOST = socket.gethostbyname(socket.gethostname())
server = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
server.bind((HOST,PORT))
def handleClient(conn, addr):
print (f"[NEW CONNECTION {addr} connected. ")
connected = True
while connected:
conn.send()
def start():
server.listen()
while True:
conn, addr = server.accept()
thread = threading.Thread(target=handleClient, args=(conn,addr))
thread.start()
print(f"[ACTIVE CONNECTIONS] {threading.activeCount()} ")
print ("server is starting...")
start()

client.send("bGET /suc.txt HTTP/1.1\r\nHost:127.0.0.1\r\n\r\n")
The "b..." should be b"...", i.e. you want to specify a sequence of bytes and not a string with a b as first character.
I do not how to return the file suc.txt to the client from the server side
You basically ask very broadly how to read an HTTP request, extract information from it, create a proper response and send it. All what you code so far does is create a listener socket, so you are far away from your ultimate goal.
There are two major ways to tackle this: the easy one is to use a library like http.server to implement the complexity of HTTP for you. The documentation contains actual examples on how to do this and there are many more examples on the internet for this.
The harder option is to study the actual HTTP standard and implement everything yourself based on this standard. Expecting that somebody explains the complex standard here and describes how to implement it would be a too broad question.

Why can't I connect to this websocket?

Having great difficulty getting a response, even a reassuring error response, after attempts to connect to Coinfloor's websocket API. Docs here: https://github.com/coinfloor/API/blob/master/WEBSOCKET-README.md
'Commands, replies, and notifications traverse the WebSocket in text
frames with JSON-formatted payloads.'
Here is my attempt:
import socket
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
server = 'api.coinfloor.co.uk'
port = 443
server_ip = socket.gethostbyname('api.coinfloor.co.uk')
payload = '{"method": "WatchTicker","base": int("0xF800", 16),"counter":int("0xFA20",16),"watch":True}'
s.connect((server_ip, port))
s.sendall(payload.encode('utf-8'))
result = s.recv(4096)
print(result)
It just returns this:
b''
i.e. an empty byte string.

Because sockets and WebSocket are completely different things. AF_INET/SOCK_STREAM socket is a facility that uses TCP to communicate to the remote peer. On the other hand, WebSocket is a binary protocol that
Works on the top of TCP or TLS.
Has to perform HTTP handshake before data exchange.
Since WebSocket is a rather complex protocol (see the standard), your best course of action is to find a WebSocket library and use it instead of trying to implement the protocol starting from TCP.

Python decrypt TLS traffic

I'm trying to decode SIP TLS v1.0 traffic which uses a known port (TCP 5061).
I do have access to my private key to extract the information (TCP raw data)
I have created my code to access TCP traffic and I can read that info right now.
packet = socket.recv(sipLocatorConfig.NETWORK_TCP_MAX_SIZE)
My goal is to be able to read encrypted traffic (which I can already) and decrypt it with my private key so I can analyze it after that.
How to convert TLS to TCP/raw data? I was able to start SSL Server, but how to parse raw data using SSL library.
import socket
from OpenSSL import SSL
context = SSL.Context(SSL.SSLv23_METHOD)
context.use_privatekey_file('key')
context.use_certificate_file('cert')
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s = SSL.Connection(context, s)
s.bind(('', 12345))
s.listen(5)
(connection, address) = s.accept()
while True:
print repr(connection.recv(65535))

Writing a python script to decrypt the raw capture is a huge task. I suggest you give wireshark a try, it is a graphical network analyzer that can already decrypt SSL / TLS when you have the key.
Keep in Mind: Perfect forward secrecy can prevent decryption in both wireshark and scripts. See Decrypting HTTPS traffic in Wireshark not working

Python Socket errno 10054 only when client.py runs

There are some other posts about this issue but none did help me with mine.
I'm trying to build a total simple server - client relationship in python
server.py
#!/usr/bin/python
import socket
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind(("127.0.0.1",8889))
s.listen(1)
try:
while True:
client, add = s.accept()
data = client.recv(1024)
if not data:
print 'No data'
print data
finally:
s.close()
client.py
#!/usr/bin/python
import socket
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect(("127.0.0.1",8889))
try:
while True:
message = 'Foo'
s.send(message)
ans = s.recv(1024)
print ans
finally:
s.close()
I start by running the server first, but when I try to run the client I'm getting this Errno 10054 --> An existing connection was forcibly closed by the remote host
While request the browser with the ip and the related port, I receive some data.
I'm quiet new to networking, so please explain what might be obvious wrong in my code.
EDIT* Main issue is, that the client is somehow wrong, because it returns also an empty string on recv
Thank you in advance

Main issue is, that the client is somehow wrong, because it returns also an empty string on recv
The client isn't receiving anything from the server because the server is not sending anything.
On the server side, after print data, adding client.send(data) will send the string back to the client.

I am guessing:
The server accepts one socket and then does
client, add = s.accept()
data = client.recv(1024)
...
client, add = s.accept()
The client does this in the mean time:
s.send(message)
ans = s.recv(1024) # blocks until timeout
If now an other client connects to the server then client is replaced, the socket garbage collected and closed. s.recv(1024) will then tell that the connection is reset.
Have a look at import select or twisted (google around) to handle multiple connections at once.