如何为 django 日期时间 model 字段设置默认值和 auto_now 值

Question

I want to set a default DateTime for my Django model that will be used in querying data from google fit api. Since this field will be empty in the beginning, the default value will allow for the first query and the auto_now will keep updating as more queries are made. Django seems not to allow both auto_now and default as arguments. Could anyone please assist with a workaround I could use to achieve this?

models.py

class GoogleStep(models.Model):
    user = models.OneToOneField(User, related_name='googlestep', on_delete=models.CASCADE)
    starttime = models.DateField(null=False)
    endtime = models.DateField(null=False)
    steps = models.IntegerField(null=False)
    last_sync = models.DateTimeField(auto_now=True, null=False)

    class Meta:
       ordering = ('-starttime',)

Answer 1

last_sync = models.DateTimeField(auto_now_add=True, null=False)