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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 discover_connections(self, x=255, y=255):
 """Attempt to discover all available Ethernet connections to a machine. After calling this method, :py:class:`.MachineController` will attempt to communicate via the Ethernet connection on the same board as the destination chip for all commands. If called multiple times, existing connections will be retained in preference to new ones. .. note:: The system must be booted for this command to succeed. .. note:: Currently, only systems comprised of multiple Ethernet-connected SpiNN-5 boards are supported. Parameters x : int y : int (Optional) The coordinates of the chip to initially use to query the system for the set of live chips. Returns ------- int The number of new connections established. """

        working_chips = set(
            (x, y)
            for (x, y), route in iteritems(self.get_p2p_routing_table(x, y))
            if route != consts.P2PTableEntry.none)
        self._width = max(x for x, y in working_chips) + 1
        self._height = max(y for x, y in working_chips) + 1

        num_new_connections = 0

        for x, y in spinn5_eth_coords(self._width, self._height,
                                      *self.root_chip):
            if (x, y) in working_chips and (x, y) not in self.connections:
                # Discover the chip's IP address
                try:
                    ip = self.get_ip_address(x, y)
                except SCPError:
                    continue

                if ip is not None:
                    # Create a connection to the IP
                    self.connections[(x, y)] = \
                        SCPConnection(ip, self.scp_port,
                                      self.n_tries, self.timeout)

                    # Attempt to use the connection (and remove it if it
                    # doesn't work)
                    try:
                        self.get_software_version(x, y, 0)
                        num_new_connections += 1
                    except SCPError:
                        self.connections.pop((x, y)).close()

        return num_new_connections