{'t1': str(datetime.datetime.today()), 't2': str(datetime.date.today())}

 raise TypeError("Object of type '%s' is not JSON serializable" % o.__class__.__name__)

d1 = {'t1': datetime.datetime.today(), 't2': datetime.date.today()}
res = json.dumps(d1, cls=MyJsonEncoder)
print(res)

class Student(object):
    school = '清华大学'
    __label = '逆来顺受'  # 由于python崇尚自由 所以并没有真正的隐藏  而是自动转换成了特定的语法
    def __inIT__(self, name, age):
        self.name = name
        self.age = age
    def choose_course(self):
        print('%s正在选课'%self.name)
stu1 = Student('jason', 18)
print(stu1.school)  # 清华大学
print(stu1.name)  # jason
print(stu1.age)  # 18
print(stu1.__label) # 报错
print(Student.__dict__)  # '_Student__label': '逆来顺受'
print(Student._Student__label) # 逆来顺受
print(stu1._Student__label) # 逆来顺受

class Student(object):
    __school = '清华大学'
    def __init__(self, name, age):
        self.__name = name
        self.__age = age
    # 专门开设一个访问学生数据的通道(接口)
    def check_info(self):
        print("""
        学生姓名:%s
        学生年龄:%s
        """ % (self.__name, self.__age))
    # 专门开设一个修改学生数据的通道(接口)
    def set_info(self,name,age):
        if len(name) == 0:
            print('用户名不能为空')
            return
        if not isinstance(age,int):
            print('年龄必须是数字')
            return
        self.__name = name
        self.__age = age

stu1 = Student('jason', 18)
stu1.check_info()
stu1.set_info('jasonNB',28)
stu1.check_info()
stu1.set_info('','haha')

class Person(object):
    def __init__(self, name, height, weight):
        self.__name = name
        self.height = height
        self.weight = weight
    @property
    def BMI(self):
        # print('%s的BMI指数是:%s' % (self.name, self.weight / (self.height ** 2)))
        return '%s的BMI指数是:%s' % (self.__name, self.weight / (self.height ** 2))

p1 = Person('jason', 1.83, 77)
# p1.BMI() # 22.9
print(p1.BMI)
p2 = Person('eason',1.90,85)
# p2.BMI()  # 23.5
print(p2.BMI)
P3 = Person('xd',1.85,100)
# p3.BMI()  # 29.2
print(p3.BMI)
p4 = Person('xd',1.5,34)
# p4.BMI()  # 15.1
print(p4.BMI)

class Animal(object):
    def speak(self):
        pass

class Cat(Animal):
      def speak(self):
          print('喵喵喵')

class Dog(Animal):
      def speak(self):
          print('汪汪汪')

class Pig(Animal):
      def speak(self):
          print('哼哼哼')

c1 = Cat()
d1 = Dog()
p1 = Pig()
c1.speak()
d1.speak()
p1.speak()

import abc
# 指定metaclass属性将类设置为抽象类，抽象类本身只是用来约束子类的，不能被实例化
class Animal(metaclass=abc.ABCMeta):
    @abc.abstractmethod # 该装饰器限制子类必须定义有一个名为talk的方法
    def talk(self): # 抽象方法中无需实现具体的功能
        pass
class Person(Animal): # 但凡继承Animal的子类都必须遵循Animal规定的标准
    def talk(self):
        pass
p1=Person() # 若子类中没有一个名为talk的方法则会抛出异常TypeError，无法实例化

class Memory(object):
    def read(self):
        pass
    def write(self):
        pass
class disk(object):
    def read(self):
        pass
    def write(self):
        pass

class Student(object):
    school = '清华大学'
    def get(self):
        pass

guess_name = input('请输入你想要查找的名字>>>:').strip()
  # 不使用反射不太容易实现
print(hasattr(Student, 'school'))  # True
print(hasattr(Student, 'get'))  # True
print(hasattr(Student, 'post'))  # False

print(getattr(Student, 'school'))  # 清华大学
print(getattr(Student, 'get'))  # <function Student.get at 0X10527a8c8>

guess_name = input('请输入你想要查找的名字>>>:').strip()
if hasattr(Student, guess_name):
     target_name = getattr(Student, guess_name)
     if callable(target_name):
         print('类中有一个功能名字是%s'%guess_name,target_name)
     else:
         print('类中有一个数据名字是%s'%guess_name,target_name)
else:
     print('类中没有该名字')

setattr(Student,'level','贵族学校')
print(Student.__dict__)

import settings
dir(settings)  # 获取对象中所有可以使用的名字
getattr(settings, 'NAME')

class FtpServer:
     def serve_forever(self):
         while True:
             inp=input('input your cmd>>: ').strip()
             cmd,file=inp.split()
             if hasattr(self,cmd): # 根据用户输入的cmd，判断对象self有无对应的方法属性
                 func=getattr(self,cmd) # 根据字符串cmd，获取对象self对应的方法属性
                 func(file)
     def get(self,file):
         print('Downloading %s...' %file)
     def put(self,file):
         print('Uploading %s...' %file)

obj = FtpServer()
obj.serve_forever()