from django.db import models
import random
import string

# Create your models here.
class Student(models.Model):
    name = models.CharField(max_length=30)
    age = models.ImageField()
    sex = models.ImageField(choices=((1,'男'),(2,'女')),default=1)
    card_no = models.CharField(max_length=18)

    @classmethod
    def insert_student_data(cls,num):
        '''
        num: 批量插入的记录条数
       '''
        def random_str(str,length):
            return ''.join(random.choices(str,k=length))
        student_list = []
        for i in range(num):
            student_list.append(Student(
                name=random_str(string.ascii_lowercase,10),
                age=random.randint(18,30),
                sex=random.choice([1,2]),
                card_no=random_str(string.digits,18)                    
                ))
        Student.objects.bulk_create(student_list)