code: def get_levels():
          
          levels = ffi.new('cairo_ps_level_t const **')
          num_levels = ffi.new('int *')
          cairo.cairo_ps_get_levels(levels, num_levels)
          levels = levels[0]
          return [levels[i] for i in range(num_levels[0])]
docs: Return the list of supported PostScript levels.
          See :meth:`restrict_to_level`.
  
          :return: A list of :ref:`PS_LEVEL` strings.