定义徽章 后， 只需将信号与sender = Badge连接，测试示例：
from django.db import modelsfrom django.db.models import signalsdef create_badge(sender, instance, created, **kwargs): print "Post save emited for", instanceclass BadgeCategory(models.Model): name = models.CharField(max_length=100)class Badge(models.Model): name = models.CharField(max_length=16, help_text="Name for Badge") category = models.ForeignKey(BadgeCategory, help_text="Category for badge") description = models.CharField(max_length=32, help_text="A brief description")signals.post_save.connect(create_badge, sender=Badge)
测试外壳会话：
In [1]: category = BadgeCategory(name='foo')In [2]: category.save()In [3]: badge = Badge(category=category, name='bar', description='test badge')In [4]: badge.save()Post save emited for Badge object
