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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def prepare(self):
 """Prepare server to serving requests. It binds a socket's port, setups the socket to ``listen()`` and does other preparing things. """

        self._interrupt = None

        if self.software is None:
            self.software = '%s Server' % self.version

        # Select the appropriate socket
        self.socket = None
        msg = 'No socket could be created'
        if os.getenv('LISTEN_PID', None):
            # systemd socket activation
            self.socket = socket.fromfd(3, socket.AF_INET, socket.SOCK_STREAM)
        elif isinstance(self.bind_addr, six.string_types):
            # AF_UNIX socket
            try:
                self.bind_unix_socket(self.bind_addr)
            except socket.error as serr:
                msg = '%s -- (%s: %s)' % (msg, self.bind_addr, serr)
                six.raise_from(socket.error(msg), serr)
        else:
            # AF_INET or AF_INET6 socket
            # Get the correct address family for our host (allows IPv6
            # addresses)
            host, port = self.bind_addr
            try:
                info = socket.getaddrinfo(
                    host, port, socket.AF_UNSPEC,
                    socket.SOCK_STREAM, 0, socket.AI_PASSIVE,
                )
            except socket.gaierror:
                sock_type = socket.AF_INET
                bind_addr = self.bind_addr

                if ':' in host:
                    sock_type = socket.AF_INET6
                    bind_addr = bind_addr + (0, 0)

                info = [(sock_type, socket.SOCK_STREAM, 0, '', bind_addr)]

            for res in info:
                af, socktype, proto, canonname, sa = res
                try:
                    self.bind(af, socktype, proto)
                    break
                except socket.error as serr:
                    msg = '%s -- (%s: %s)' % (msg, sa, serr)
                    if self.socket:
                        self.socket.close()
                    self.socket = None

        if not self.socket:
            raise socket.error(msg)

        # Timeout so KeyboardInterrupt can be caught on Win32
        self.socket.settimeout(1)
        self.socket.listen(self.request_queue_size)

        # Create worker threads
        self.requests.start()

        self.ready = True
        self._start_time = time.time()