如何在Django中创建查找？

from django.db import models

class Person(models.Model):
    first_name = models.CharField(max_length=30)
    last_name = models.CharField(max_length=30)
    age = models.IntegerField()

from myapp.models import Person

# 创建一个新的Person对象
person = Person.objects.create(first_name="John", last_name="Doe", age=30)

# 保存对象到数据库
person.save()

# 查找所有的Person对象
all_persons = Person.objects.all()

# 查找指定的Person对象
john = Person.objects.get(first_name="John", last_name="Doe")

# 根据年龄筛选Person对象
adults = Person.objects.filter(age__gte=18)

# 根据姓氏排序
sorted_persons = Person.objects.order_by('last_name')

# 更新Person对象
john.age = 31
john.save()

# 删除Person对象
john.delete()