当值为空时如何告诉cqlengine不考虑min_length

Question

对于非必填字段，当为带有None的可选字段设置min_length={n}值时，将引发以下异常：

cassandra.cqlengine.ValidationError: {field} is shorter than {n} characters

示例：

class Users(Model):
    id = columns.TimeUUID(primary_key=True, partition_key=True, default=uuid.uuid1)
    first_name = columns.Text(max_length=50)
    last_name = columns.Text(max_length=50)
    name = columns.Text(max_length=30, min_length=4, required=False)

Users.create(first_name='first', last_name='last')

  

cassandra.cqlengine.ValidationError：名称少于4个字符

我的问题是，当值为min_length时如何阻止None的验证