docs: def hline(level, **kwargs):
      """Draws a horizontal line at the given level.
  
      Parameters
      ----------
      level: float
          The level at which to draw the horizontal line.
      preserve_domain: boolean (default: False)
          If true, the line does not affect the domain of the 'y' scale.
      """
      kwargs.setdefault('colors', ['dodgerblue'])
      kwargs.setdefault('stroke_width', 1)
      scales = kwargs.pop('scales', {})
      fig = kwargs.get('figure', current_figure())
      scales['x'] = fig.scale_x
  
      level = array(level)
      if len(level.shape) == 0:
          x = [0, 1]
          y = [level, level]
      else:
          x = [0, 1]
          y = column_stack([level, level])
      return plot(x, y, scales=scales, preserve_domain={
          'x': True,
          'y': kwargs.get('preserve_domain', False)
      }, axes=False, update_context=False, **kwargs)