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Server implementation with python socket and port forwarding

I've been trying to implement a server-client connection, here is my code-
Server.py
import socket
server = socket.socket()
server.bind(('', 2112))
server.listen(5)
print('Server created with port 2112')
server.accept()
print('Connected')
Client.py
import socket
##Public_IP is the Public IP address of my router
client = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
client.connect((Public_IP, 2112))
Both Server.py and Client.py are running on my computer(server). It works just fine when I replace Public_IP with '192.168.0.143', but when I use Public_IP, it gives the following error-
TimeoutError: [WinError 10060] A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond
Is it because I'm running both Server.py and Client.py on the same computer? Please let me know what I'm doing wrong.
Setting up port forwarding -
Public IP
Port forwarding
Private IP address of server
I followed this tutorial for setting up port forwarding.
I also tried replacing the empty string in Server.py with my private IP address-
server.bind(('192.168.0.143', 2112))
Edit: I have tried-
Running Client.py externally (on a different LAN) with firewall down on both the ends, but didn't make any difference (it gave a timeout error).
Running Client.py on the same LAN with firewall down, that seemed to work fine.
Running the Client.py on the same device also worked fine with the firewall down.

Socket Programming - How to connect a remote address

I am practicing socket programming using python. I am fimiliar with how to make a simple tcp server and client in local address but I want to know how to make it possible so that I can connect to my own computer from a client app that I built. What modifications do I have to make in this server script? or client?
server:
import socket
s = socket.socket(socket.AF_INET,socket.SOCK_STREAM)
#The host is set to be the local machine.
address = ("127.0.0.1",1234)
s.bind(address)
s.listen(1)
c , addr = s.accept()
while True:
#do some stuff
c.close()
client:
import socket
s = socket.socket(socket.AF_INET,socket.SOCK_STREAM)
address = ("127.0.0.1",1234)
s.connect(address)
while True:
#Do client stuff
s.close()

I'm not allowed to make comments yet. But if you have a client app on another device, you can make the HOST your machines IP that stores the server. IF you're using windows ENTER: ipconfig In your command line argument. I think that or Linux its if config. You should be able to set your address to your machines ip address in order to get the client to connect to your local machine. As you noted, localhost will not work.

Connect to python server in different network

My port forward rule
I've created a python TCP server and client which is working fine when I launch both server and client on my computer and when I launch the server and the client on different computers on the same network, however I wanted to make it work when computers are in different networks. I have forwarded my router port 8080 to convert to 8888 in my computer, in fact I have also a rule for the port 80 on my router converting to 8080 on my PC which is the Wamp server, and as the python server is not working I guessed it was from the code but I can't figure it out:
Server:
import socket
sck = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sck.bind(("127.0.0.1", 8888))
sck.listen(1)
conn, adr = sck.accept()
print('Connected to ', adr)
while 1:
data = conn.recv(1024).decode()
if data and ('over' not in data):
conn.send(data.encode())
continue
break
conn.close()
Client:
import socket
sck = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sck.connect(('<my_external_ip>', 8888))
while True:
data = input('Say something: ')
if 'Shut up' in data:
sck.send('over'.encode())
sck.close
break
sck.send(data.encode())
I've made this test:
Started Wamp server and tried to access it by my external ip with chrome (working)
Opened my Python TCP Client and connected to the Wamp server (working)
Turned Wamp off and started my python server with the same port as Wamp, then tried to acess with the python client (not working)
If there's nothing wrong with the TCP Server code why does Wamp work and he don't? Please check the following - Whats the logic behind binding 127.0.0.1 I couldn't understand... Won't that make it only be accessible by my PC?
If that part is ok than at least is something related to the Server code I guess...

Python client can not communicate with ruby server. I get [Errno 10061] No connection could be made because the target machine actively refused it

I have the intention of running machine learning algorithms written in Python on data in a database of a Ruby on Rails app. After some research I have discovered sockets and therefore created a Ruby server and Python client. I am running them both on two different command prompt terminals.
Here is the Ruby server code:
require "socket"
server = TCPServer.open(2000)
loop {
client = server.accept
client.puts(Time.now.ctime)
client.puts "Closing the connection. Bye!"
client.close
}
Here is the Python client code:
import socket
s = socket.socket()
host = "localhost"
port = 2000
s.connect((host , port))
I do not understand where the problem is. Kindly assist.

Given insightful answers to my question above the code Ruby server and Python client should be as below.
For the Ruby server:
require "socket" # Get sockets from stdlib
server = TCPServer.open("127.0.0.1" , 2000) # Socket to listen on port 2000
loop { # Server runs forever
client = server.accept # Wait for a client to connect
client.puts(Time.now.ctime) # Send the time to the client
client.puts "Closing the connection. Bye!"
client.close # Disconnect from the client
}
For the Python client:
import socket # Import socket module
s = socket.socket() # Create a socket object
host = "127.0.0.1"
port = 2000 # Reserve a port for your service.
s.connect((host , port))
print s.recv(1024)
s.close() # Close the socket when done
The open() method of the TCPServer class in Ruby takes two parameters. The first being the host name and the second the port i.e
TCPServer.open(hostname , port)

Python Sockets: Connection Timeout

I'm trying to write two short python scripts that will connect two or more machines to each other, one as the server and the others as clients. It worked perfectly when testing the client and the server script on the same computer, but when I tried it from another computer the client kept timing out; it couldn't connect to the server. Here's my server code:
import socket
server = socket.socket()
host = "computername"
port = 12345
server.bind((host, port))
server.listen(5)
client, addr = server.accept()
Client code:
import socket
server = socket.socket()
host = "computername"
port = 12345
server.connect((host, port))
Any clue as to why the machines can't connect?

I think, you are changing host variable properly when running both client and server scripts in different machines. Try by changing that properly/or using IP address of server machine.

The communication could be prohibited by a firewall.
To rule out DNS related problem, try IPs instead of hostnames:
# server: listen on all interfaces
server.bind(('', port))
and:
# client: specify server's IP address
server.connect(("192.168.XX.YY", port))
with a real IP address, of course.