docs: def _set_label(label, mark, dim, **kwargs):
      """Helper function to set labels for an axis
      """
      if mark is None:
          mark = _context['last_mark']
      if mark is None:
          return {}
      fig = kwargs.get('figure', current_figure())
      scales = mark.scales
      scale_metadata = mark.scales_metadata.get(dim, {})
      scale = scales.get(dim, None)
      if scale is None:
          return
      dimension = scale_metadata.get('dimension', scales[dim])
      axis = _fetch_axis(fig, dimension, scales[dim])
  
      if axis is not None:
          _apply_properties(axis, {'label': label})