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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 _get_connection(self, x, y):
 """Get the appropriate connection for a chip."""

        if (self._width is None or self._height is None or
                self._root_chip is None):
            return self.connections[None]
        else:
            # If possible, use the local Ethernet connected chip
            eth_chip = spinn5_local_eth_coord(x, y, self._width, self._height,
                                              *self._root_chip)
            conn = self.connections.get(eth_chip)
            if conn is not None:
                return conn
            else:
                # If no connection was available to the local board, choose
                # another arbitrarily.
                # XXX: This choice will cause lots of contention in systems
                # with many missing Ethernet connections.
                return self.connections[None]