如何从另一个模型中操作一个模型字段的值?

I have two models

我有两个模型

class Employee(models.Model):
    name = models.CharField(max_length=20)
    ID = models.IntegerField()
    basic_salary = models.IntegerField()     
    total_leave = models.IntegerField(default = 14)
    paid_leave = models.IntegerField(default = 0)
    unpaid_leave = models.IntegerField(default = 0)

def __str__(self):
    return self.name

class Leave_management(models.Model):

    name = models.OnetoOneField(Employee,on_delete= models.CASCADE)
    reason = models.CharField(max_length=50)
    from = models.DateTimeField()
    to = models.DateTimeField()
    total_days = models.IntegerField()

     def __str__(self):
        return self.name
class Employee(mo