old_contents: 
  from django.template.loader import get_template
  from django.test import SimpleTestCase
  
  from .utils import TemplateTestMixin
  
  
  class TestFieldTag(TemplateTestMixin, SimpleTestCase):
      TEMPLATES = {
          'field': '{% load sniplates %}{% form_field form.field %}'
      }
  
      def test_field_tag(self):
          '''
          Make sure the field tag is usable.
          '''
          tmpl = get_template('field')
          output = tmpl.render(self.ctx)
  
new_contents: 
  from django import forms
  from django.template.loader import get_template
  from django.test import SimpleTestCase
  
  from .utils import TemplateTestMixin
  
  
  class TestForm(forms.Form):
      char = forms.CharField()
  
  
  class TestFieldTag(TemplateTestMixin, SimpleTestCase):
      TEMPLATES = {
          'widgets': '''{% block CharField %}<input type="text" name="{{ name }}" value="{{ value|default:'' }}>{% endblock %}''',
          'field': '{% load sniplates %}{% load_widgets form="widgets" %}{% form_field form.char %}'
      }
      def setUp(self):
          super(TestFieldTag, self).setUp()
          self.ctx['form'] = TestForm()
  
      def test_field_tag(self):
          '''
          Make sure the field tag is usable.
          '''
          tmpl = get_template('field')
          output = tmpl.render(self.ctx)
  
subject: Make first field test work