docs: def get_machine(self, x=255, y=255, default_num_cores=18):
          """**Deprecated.** Probe the machine to discover which cores and links
          are working.
  
          .. warning::
              This method has been deprecated in favour of
              :py:meth:`.get_system_info` for getting information about the
              general resources available in a SpiNNaker machine. This method may
              be removed in the future.
  
              To build a :py:class:`~rig.place_and_route.Machine` for
              place-and-route purposes, the
              :py:func:`rig.place_and_route.utils.build_machine` utility function
              may be used with :py:meth:`.get_system_info` like so::
  
                  >> from rig.place_and_route import build_machine
                  >> sys_info = mc.get_system_info()
                  >> machine = build_machine(sys_info)
  
              This method also historically used the size of the SDRAM and
              SRAM heaps to set the respective resource values in the
              :py:class:`~rig.place_and_route.Machine`. :py:meth:`.get_machine`
              since changed to reporting the size of the largest free block in
              the SDRAM and SRAM heaps on each chip. Most applications should not
              be negatively impacted by this change.
  
          .. note::
              The chip (x, y) supplied is the one where the search for working
              chips begins. Selecting anything other than (255, 255), the
              default, may be useful when debugging very broken machines.
  
          Parameters
          ----------
          default_num_cores : int
              This argument is ignored.
  
          Returns
          -------
          :py:class:`~rig.place_and_route.Machine`
              This Machine will include all cores reported as working by the
              system software with the following resources defined:
  
              :py:data:`~rig.place_and_route.Cores`
                  Number of working cores on each chip (including the monitor
                  core, any cores already running applications and idle cores).
              :py:data:`~rig.place_and_route.SDRAM`
                  The size of the largest free block of SDRAM on the heap. This
                  gives a conservative measure of how much SDRAM is free on a
                  given chip (which will underestimate availability if the
                  system's memory is highly fragmented.
              :py:data:`~rig.place_and_route.SRAM`
                  The size of the largest free block of SRAM on the heap. This
                  gives a conservative measure of how much SRAM is free on a
                  given chip (which will underestimate availability if the
                  system's memory is highly fragmented.
          """
          warnings.warn(
              "MachineController.get_machine() is deprecated, "
              "see get_system_info().", DeprecationWarning)
  
          from rig.place_and_route.utils import build_machine
  
          system_info = self.get_system_info(x, y)
          return build_machine(system_info)