old_contents: from django import template
  from django.utils.html import mark_safe
  
  register = template.Library()
  
  
  @register.simple_tag(takes_context=True)
  def render_plugin(context, plugin):
      """
      Render a single plugin. See :mod:`feincms3.renderer` for additional
      details.
      """
      return context['renderer'].render_plugin_in_context(plugin, context)
  
  
  @register.simple_tag(takes_context=True)
  def render_plugins(context, plugins):
      """
      Render and concatenate a list of plugins. See
      :mod:`feincms3.renderer` for additional details.
      """
      renderer = context['renderer']
      return mark_safe(''.join(
          renderer.render_plugin_in_context(plugin, context)
          for plugin in plugins
      ))
  
  
  @register.simple_tag(takes_context=True)
  def render_region(context, regions, region, **kwargs):
      """
      Render a single region. See :class:`~feincms3.renderer.Regions` for
      additional details. Any and all keyword arguments are forwarded to the
      ``render`` method of the ``Regions`` instance.
      """
      return regions.render(region, context, **kwargs)
  
new_contents: from django import template
  from django.utils.html import mark_safe
  
  register = template.Library()
  
  
  @register.simple_tag(takes_context=True)
  def render_plugin(context, plugin):
      """
      Render a single plugin. See :mod:`feincms3.renderer` for additional
      details.
  
      In general you should prefer
      :func:`~feincms3.templatetags.feincms3_renderer.render_region` over this
      tag.
      """
      return context['renderer'].render_plugin_in_context(plugin, context)
  
  
  @register.simple_tag(takes_context=True)
  def render_plugins(context, plugins):
      """
      Render and concatenate a list of plugins. See
      :mod:`feincms3.renderer` for additional details.
  
      In general you should prefer
      :func:`~feincms3.templatetags.feincms3_renderer.render_region` over this
      tag.
      """
      renderer = context['renderer']
      return mark_safe(''.join(
          renderer.render_plugin_in_context(plugin, context)
          for plugin in plugins
      ))
  
  
  @register.simple_tag(takes_context=True)
  def render_region(context, regions, region, **kwargs):
      """
      Render a single region. See :class:`~feincms3.renderer.Regions` for
      additional details. Any and all keyword arguments are forwarded to the
      ``render`` method of the ``Regions`` instance.
      """
      return regions.render(region, context, **kwargs)
  
subject: Add note to render_plugin[s] that render_region should be preferred