old_contents: # -*- encoding: utf-8 -*-
  from __future__ import unicode_literals
  
  from django import template
  from django.utils.safestring import mark_safe
  from django.utils.timezone import make_naive, UTC
  
  REGISTER = template.Library()
  
  
  @REGISTER.filter(is_safe=True)
  @REGISTER.simple_tag(name="tisoformat")
  def tisoformat(date):
      return mark_safe(make_naive(date, UTC()).replace(microsecond=0).isoformat()+'Z')
  
new_contents: # -*- encoding: utf-8 -*-
  from __future__ import unicode_literals
  
  from django import template
  from django.utils.safestring import mark_safe
  from django.utils.timezone import make_naive, UTC
  
  register = template.Library()
  
  
  @register.filter(is_safe=True)
  @register.simple_tag(name="tisoformat")
  def tisoformat(date):
      return mark_safe(make_naive(date, UTC()).replace(microsecond=0).isoformat()+'Z')
  
subject: Fix register case