更新第四章

data/1.python初阶/4.面向对象编程/1.类和对象的概念/student.json

 {
-  "multiline": [
-    {
-      "__init__": "init"
-    },
-    {
-      "dump(self)": "dump()"
-    },
-    {
-      "s = Student": "s = new Student"
-    }
-  ],
-  "source": "student.py",
+  "source": "student.md",
   "depends": [],
   "exercise_id": 56,
-  "type": "code_options"
+  "type": "code_options",
+  "author": "huanhuilong",
+  "notebook_enable": true
 }
\ No newline at end of file

data/1.python初阶/4.面向对象编程/1.类和对象的概念/student.md

+# Python 类和对象
+
+创建学生类, 创建一个学生列表，加入3个学生，循环打印学生信息
+
+```python
+# -*- coding: UTF-8 -*-
+class Student:
+    def __init__(self, no, name, age):
+        # TODO(You): 请在此初始化成员
+
+    def dump(self):
+        # TODO(You): 请在此打印学生信息
+
+if __name__ == '__main__':
+    students = []
+    for i in range(0, 3):
+        s = Student(i, f'somebody_{i}', 20+i)
+        students.append(s)
+
+    for s in students:
+        print('')
+        s.dump()
+```
+
+请选出下列对Student**实现不正确**的代码。
+
+## template
+
+```python
+class Student:
+    def __init__(self, no, name, age):
+        self.no = no
+        self.name = name
+        self.age = age
+
+    def dump(self):
+        print(f"* no:{self.no}")
+        print(f"* name:{self.name}")
+        print(f"* age:{self.age}")
+
+if __name__ == '__main__':
+    students = []
+    for i in range(0, 3):
+        s = Student(i, f'somebody_{i}', 20+i)
+        students.append(s)
+    for s in students:
+        s.dump()
+```
+
+## 答案
+
+```python
+class Student:
+    def __init__(self, no, name, age):
+        self.no = no
+        self.name = name
+        self.age = age
+
+    def dump():
+        print(f"* no:{self.no}")
+        print(f"* name:{self.name}")
+        print(f"* age:{self.age}")
+```
+
+## 选项
+
+### A
+
+```python
+class Student:
+    def __init__(self, no, name, age):
+        self.no = no
+        self.name = name
+        self.age = age
+
+    def dump(self):
+        print(f"* no:{self.no}")
+        print(f"* name:{self.name}")
+        print(f"* age:{self.age}")
+```
+
+### B
+
+```python
+class Student:
+    def __init__(self, no, name, age):
+        self.no = no
+        self.name = name
+        self.age = age
+
+    def dump(self):
+        infos = [
+            f"* no:{self.no}",
+            f"* name:{self.name}",
+            f"* age:{self.age}"
+        ]
+        for info in infos:
+            print(info)
+```
+
+### C
+
+```python
+class Student:
+    def __init__(self, no, name, age):
+        self.fields = {
+            'no': no,
+            'name': name,
+            'age': age
+        }
+
+    def dump(self):
+        for field_name in self.fields:
+            field_value = self.fields[field_name]
+            print(f'* {field_name}:{field_value}')
+```

data/1.python初阶/4.面向对象编程/2.类成员/student.json

 {
-  "multiline": [
-    {
-      "no,": "_no"
-    },
-    {
-      "self.name = name": "self.name = _name"
-    },
-    {
-      "s.age": "s.age()"
-    }
-  ],
-  "source": "student.py",
+  "source": "student.md",
   "depends": [],
   "exercise_id": 54,
-  "type": "code_options"
+  "type": "code_options",
+  "author": "huanhuilong",
+  "notebook_enable": true
 }
\ No newline at end of file

data/1.python初阶/4.面向对象编程/2.类成员/student.md

+# Python 类成员
+
+类成员变量可以直接访问，直接调用学生类的成员变量，打印学生信息
+
+```python
+# -*- coding: UTF-8 -*-
+class Student:
+    # TODO(You): 请在此实现含有no/name/age 三个成员属性的学生类
+
+def test():
+    students = []
+    for i in range(0, 3):
+        s = Student(i, f'somebody_{i}', 20+i)
+        students.append(s)
+
+    for s in students:
+        print('')
+        print(f"* no:{s.no}")
+        print(f"* name:{s.name}")
+        print(f"* age:{s.age}")
+
+if __name__ == '__main__':
+    test()
+```
+
+以下对Student的实现， **功能不正确** 的代码是？。
+
+## template
+
+```python
+class Student:
+    def __init__(self, no, name, age):
+        self.no = no
+        self.name = name
+        self.age = age
+
+def test():
+    students = []
+    for i in range(0, 3):
+        s = Student(i, f'somebody_{i}', 20+i)
+        students.append(s)
+
+    for s in students:
+        print('')
+        print(f"* no:{s.no}")
+        print(f"* name:{s.name}")
+        print(f"* age:{s.age}")
+
+if __name__ == '__main__':
+    test()
+```
+
+## 答案
+
+```python
+# 普通初始化函数添加成员
+class Student:
+    def __init__(no, name, age):
+        self.no = no
+        self.name = name
+        self.age = age
+```
+
+## 选项
+
+### A
+
+```python
+# 使用 @dataclass 可以简化实现
+from dataclasses import dataclass
+
+@dataclass
+class Student:
+    no: int
+    name: str
+    age: int
+```
+
+### B
+
+```python
+# 普通初始化函数添加成员
+class Student:
+    def __init__(self, no, name, age):
+        self.no = no
+        self.name = name
+        self.age = age
+```
+
+### C
+
+```python
+# 使用 @dataclass + slot 可以简化实现并且优化内存占用
+from dataclasses import dataclass
+
+@dataclass
+class Student:
+    __slots__ = ['no', 'name', 'age']
+    no: int
+    name: str
+    age: int
+```

data/1.python初阶/4.面向对象编程/3.面向对象三要素/evolope.json

 {
-  "multiline": [
-    {
-      "get_no(self)": "get_no()",
-      "get_name(self)": "get_name()",
-      "get_age(self)": "get_age()",
-      "inc_age(self)": "inc_age()"
-    },
-    {
-      "self.age += 1": "self.age -= 1"
-    },
-    {
-      "print(s.log)": "print(s.log())"
-    }
-  ],
-  "source": "evolope.py",
+  "source": "evolope.md",
   "depends": [],
   "exercise_id": 209,
-  "type": "code_options"
+  "type": "code_options",
+  "author": "huanhuilong",
+  "notebook_enable": true
 }
\ No newline at end of file

data/1.python初阶/4.面向对象编程/3.面向对象三要素/evolope.md

+# Python 封装
+
+使用类的方法获取相关信息，可以将内部的实现细节封装起来
+
+```python
+# -*- coding: UTF-8 -*-
+class Student:
+    def __init__(self, no, name, age):
+        # TODO(初始化)
+
+    def no(self):
+        # TODO(返回编号)
+
+    def name(self):
+        # TODO(返回名字)
+
+    def age(self):
+        # TODO(返回年龄)
+
+if __name__ == '__main__':
+    s = Student(0, f'somebody', 20)
+    print(f'* {s.no()}')
+    print(f'* {s.name()}')
+    print(f'* {s.age()}')
+```
+
+以下对Student的实现，**不正确**的代码是？
+
+## template
+
+```python
+class Student:
+    def __init__(self, no, name, age):
+        self._no = no
+        self._name = name
+        self._age = age
+
+    def no(self):
+        return self._no
+
+    def name(self):
+        return self._name
+
+    def age(self):
+        return self._age
+
+if __name__ == '__main__':
+    s = Student(0, f'somebody', 20)
+    print(f'* {s.no()}')
+    print(f'* {s.name()}')
+    print(f'* {s.age()}')
+```
+
+## 答案
+
+```python
+class Student:
+    def __init__(self, no, name, age):
+        self.no = no
+        self.name = name
+        self.age = age
+
+    def no(self):
+        return self.no
+
+    def name(self):
+        return self.name
+
+    def age(self):
+        return self.age
+```
+
+## 选项
+
+### A
+
+```python
+class Student:
+    def __init__(self, no, name, age):
+        self._no = no
+        self._name = name
+        self._age = age
+
+    def no(self):
+        return self._no
+
+    def name(self):
+        return self._name
+
+    def age(self):
+        return self._age
+```
+
+### B
+
+```python
+class Student:
+    def __init__(self, no, name, age):
+        self.info = {
+            'no': no,
+            'name': name,
+            'age': age
+        }
+
+    def no(self):
+        return self.info['no']
+
+    def name(self):
+        return self.info['name']
+
+    def age(self):
+        return self.info['age']
+```
+
+### C
+
+```python
+class Student:
+    def __init__(self, no, name, age):
+        self.info =[no, name, age]
+
+    def no(self):
+        return self.info[0]
+
+    def name(self):
+        return self.info[1]
+
+    def age(self):
+        return self.info[2]
+```

data/1.python初阶/4.面向对象编程/3.面向对象三要素/inherent.json

 {
-  "multiline": [
-    {
-      "People(object)": "People : object",
-      "Student(People)": "Student : People",
-      "Teacher(People)": "Teacher : People"
-    },
-    {
-      "People(object)": "People implement object",
-      "Student(People)": "Student implement People",
-      "Teacher(People)": "Teacher implement People"
-    },
-    {
-      "super().__init__(name, age)": ""
-    }
-  ],
-  "source": "inherent.py",
+  "source": "inherent.md",
   "depends": [],
   "exercise_id": 235,
-  "type": "code_options"
+  "type": "code_options",
+  "author": "huanhuilong",
+  "notebook_enable": true
 }
\ No newline at end of file

data/1.python初阶/4.面向对象编程/3.面向对象三要素/inherent.md

+# Python 继承
+
+下面是People、Student和Teacher三个类
+
+```python
+# -*- coding: UTF-8 -*-
+class People(object):
+    def __init__(self, name, age):
+        self.name = name
+        self.age = age
+
+class Student:
+    def __init__(self, no, name, age):
+        self.name = name
+        self.age = age
+        self.no = no
+
+class Teacher:
+    def __init__(self, access_key, name, age):
+        self.name = name
+        self.age = age
+        self.access_key = access_key
+
+if __name__ == '__main__':
+    s = Student(0, f'somebody', 20)
+    t = Teacher('jladfja', 'linus', 0)
+
+    print('# 教师')
+    print(f"* name:{t.name}")
+    print(f"* age:{t.age}")
+    print('')
+    print('# 学生')
+    print(f"* no:{s.no}")
+    print(f"* name:{s.name}")
+    print(f"* age:{s.age}")
+```
+
+实际上Student 和 Teacher 可以从 People 类继承，复用实现
+请选出下列对继承对使用，**正确**的选项。
+
+## template
+
+```python
+class People(object):
+    def __init__(self, name, age):
+        self.name = name
+        self.age = age
+
+class Student(People):
+    def __init__(self, no, name, age):
+        super().__init__(name, age)
+        self.no = no
+
+class Teacher(People):
+    def __init__(self, access_key, name, age):
+        super().__init__(name, age)
+        self.access_key = access_key
+
+if __name__ == '__main__':
+    s = Student(0, f'somebody', 20)
+    t = Teacher('jladfja', 'linus', 0)
+
+    print('# 教师')
+    print(f"* name:{t.name}")
+    print(f"* age:{t.age}")
+    print('')
+    print('# 学生')
+    print(f"* no:{s.no}")
+    print(f"* name:{s.name}")
+    print(f"* age:{s.age}")
+```
+
+## 答案
+
+```python
+class Student(People):
+    def __init__(self, no, name, age):
+        super().__init__(name, age)
+        self.no = no
+
+class Teacher(People):
+    def __init__(self, access_key, name, age):
+        super().__init__(name, age)
+        self.access_key = access_key
+```
+
+## 选项
+
+### A
+
+```python
+class Student(People):
+    def __init__(self, no, name, age):
+        self.no = no
+
+class Teacher(People):
+    def __init__(self, access_key, name, age):
+        self.access_key = access_key
+```
+
+### B
+
+```python
+class Student(People):
+    def __init__(self, no, name, age):
+        super.__init__(name, age)
+        self.no = no
+
+class Teacher(People):
+    def __init__(self, access_key, name, age):
+        super.__init__(name, age)
+        self.access_key = access_key
+```
+
+### C
+
+```python
+class Student(People):
+    def __init__(self, no, name, age):
+        super(name, age)
+        self.no = no
+
+class Teacher(People):
+    def __init__(self, access_key, name, age):
+        super(name, age)
+        self.access_key = access_key
+```

data/1.python初阶/4.面向对象编程/3.面向对象三要素/poly.json

 {
-  "multiline": [
-    {
-      "super().__init__(\"student\", name, age)": ""
-    },
-    {
-      "super().__init__(\"teacher\", name, age)": ""
-    },
-    {
-      "super().infos()": "self.infos()"
-    },
-    {
-      "super().infos()": "super.infos()"
-    }
-  ],
-  "source": "poly.py",
+  "source": "poly.md",
   "depends": [],
   "exercise_id": 238,
-  "type": "code_options"
+  "type": "code_options",
+  "author": "huanhuilong",
+  "notebook_enable": true
 }
\ No newline at end of file

data/1.python初阶/4.面向对象编程/3.面向对象三要素/poly.md

+# Python 类多态
+
+Student 和 Teacher 类都继承 People 类。Student 和 Teacher 类可以动态改变 People 类的 infos 方法，添加子类新增信息。程序入口可以对它们统一处理，打印他们的基本信息
+
+```python
+# -*- coding: UTF-8 -*-
+class People:
+    def __init__(self, role, name, age):
+        self.name = name
+        self.age = age
+        self.role = role
+
+    def infos(self):
+        return [
+            f"name:{self.name}",
+            f"age:{self.age}",
+            f"role:{self.role}"
+        ]
+
+class Student(People):
+    def __init__(self, no, name, age):
+        super().__init__("student", name, age)
+        self.no = no
+
+    def infos(self):
+        # TODO(You): 请在此实现学生类 infos 方法
+
+
+class Teacher(People):
+    def __init__(self, access_key, name, age):
+        super().__init__("teacher", name, age)
+        self.access_key = access_key
+
+    def infos(self):
+        # TODO(You): 请在此实现教师类 infos 方法
+
+
+if __name__ == '__main__':
+    peoples = [
+        Teacher("ajladfjkadf", "Linus", 0)
+    ]
+
+    for i in range(0, 3):
+        s = Student(i, f'somebody_{i}', 20+i)
+        peoples.append(s)
+
+    for p in peoples:
+        print()
+        for info in p.infos():
+            print(info)
+```
+
+以下对 Student 和 Teacher 的 `infos` 方法实现正确的是？ 
+
+## template
+
+```python
+class People:
+    def __init__(self, role, name, age):
+        self.name = name
+        self.age = age
+        self.role = role
+
+    def infos(self):
+        return [
+            f"name:{self.name}",
+            f"age:{self.age}",
+            f"role:{self.role}"
+        ]
+
+
+class Student(People):
+    def __init__(self, no, name, age):
+        super().__init__("student", name, age)
+        self.no = no
+
+    def infos(self):
+        info_list = super().infos()
+        info_list.append(f'no:{self.no}')
+        return info_list
+
+
+class Teacher(People):
+    def __init__(self, access_key, name, age):
+        super().__init__("teacher", name, age)
+        self.access_key = access_key
+
+    def infos(self):
+        info_list = super().infos()
+        info_list.append(f'access_key:{self.access_key}')
+        return info_list
+
+if __name__ == '__main__':
+    peoples = [
+        Teacher("ajladfjkadf", "Linus", 0)
+    ]
+
+    for i in range(0, 3):
+        s = Student(i, f'somebody_{i}', 20+i)
+        peoples.append(s)
+    for p in peoples:
+        print()
+        for info in p.infos():
+            print(info)
+```
+
+## 答案
+
+```python
+class Student(People):
+    ...
+    def infos(self):
+        info_list = super().infos()
+        info_list.append(f'no:{self.no}')
+        return info_list
+
+class Teacher(People):
+    ...
+    def infos(self):
+        info_list = super().infos()
+        info_list.append(f'access_key:{self.access_key}')
+        return info_list
+```
+
+## 选项
+
+### A
+
+```python
+class Student(People):
+    ...
+    def infos(self):
+        info_list = super.infos()
+        info_list.append(f'no:{self.no}')
+        return info_list
+
+class Teacher(People):
+    ...
+    def infos(self):
+        info_list = super.infos()
+        info_list.append(f'access_key:{self.access_key}')
+        return info_list
+```
+
+### B
+
+```python
+class Student(People):
+    ...
+    def infos(self):
+        info_list = self.infos()
+        info_list.append(f'no:{self.no}')
+        return info_list
+
+class Teacher(People):
+    ...
+    def infos(self):
+        info_list = self.infos()
+        info_list.append(f'access_key:{self.access_key}')
+        return info_list
+```
+
+### C
+
+```python
+class Student(People):
+    ...
+    def infos(self):
+        return [f'no:{self.no}']
+
+class Teacher(People):
+    ...
+    def infos(self):
+        return [f'access_key:{self.access_key}']
+```

data/1.python初阶/4.面向对象编程/4.创建类/point.json

 {
-  "one_line": {
-    "class Point": [
-      "def class Point"
-    ],
-    "dot(self, right)": [
-      "dot(right)"
-    ],
-    "self.x*right.x+self.y*right.y+self.z*right.z": [
-      "x*right.x+y*right.y+z*right.z"
-    ],
-    "__init__": [
-      "init"
-    ],
-    "= Point": [
-      "new = Point"
-    ]
-  },
-  "source": "point.py",
+  "source": "point.md",
   "depends": [],
   "exercise_id": 52,
-  "type": "code_options"
+  "type": "code_options",
+  "author": "huanhuilong",
+  "notebook_enable": true
 }
\ No newline at end of file

data/1.python初阶/4.面向对象编程/4.创建类/point.md

+# Python 类创建
+
+创建点对象，有多种方式创建一个类的实例，我们称一个点的x、y、z都一样的点为对角点。
+
+```python
+# -*- coding: UTF-8 -*-
+class Point:
+    # TODO(You): 添加代码支持类的创建
+
+if __name__ == '__main__':
+    points = []
+
+    # TODO(You): 批量创建1000个对角点，第i个点的坐标是 (i,i,i)
+
+    for point in points:
+        print(point)
+```
+
+以下对上述代码补全，不正确的是？
+
+## template
+
+```python
+class Point:
+    def __init__(self, x, y, z):
+        self.x = x
+        self.y = y
+        self.z = z
+
+if __name__ == '__main__':
+    points = []
+    for i in range(1000):
+        points.append(Point(i,i,i))
+
+    for point in points:
+        print(point)
+```
+
+## 答案
+
+```python
+class Point:
+    def __init__(self, x, y, z):
+        self.x = x
+        self.y = y
+        self.z = z
+
+if __name__ == '__main__':
+    points = []
+    for i in range(1000):
+        points.append(new Point(i,i,i))
+```
+
+## 选项
+
+### A
+
+```python
+class Point:
+    def __init__(self, x, y, z):
+        self.x = x
+        self.y = y
+        self.z = z
+
+if __name__ == '__main__':
+    points = []
+    for i in range(1000):
+        points.append(Point(i,i,i))
+```
+
+### B
+
+```python
+# 通过 @classmethod 装饰器，增加一个类级别的创建方法，批量创建
+class Point:
+    def __init__(self, x, y, z):
+        self.x = x
+        self.y = y
+        self.z = z
+
+    @classmethod
+    def create_diag_points(cls, count):
+        # 在@classmethod修饰的方法中，其中 cls 表示 Point
+        points = []
+        for i in range(count):
+            points.append(cls(i,i,i))
+        return points
+
+if __name__ == '__main__':
+    points = Point.create_diag_points(1000)
+```
+
+### C
+
+```python
+# 添加类静态方法，批量创建对角点
+class Point:
+    def __init__(self, x, y, z):
+        self.x = x
+        self.y = y
+        self.z = z
+
+    @staticmethod
+    def create_diag_points(count):
+        points = []
+        for i in range(count):
+            points.append(Point(i,i,i))
+        return points
+
+if __name__ == '__main__':
+    points = Point.create_diag_points(1000)
+```

data/1.python初阶/4.面向对象编程/5.抽象类/abstract.json

 {
-  "one_line": {
-    "@abc.abstractmethod": [
-      "@abstractmethod"
-    ],
-    "pass": [
-      ""
-    ],
-    "import abc": [
-      ""
-    ]
-  },
-  "source": "abstract.py",
+  "source": "abstract.md",
   "depends": [],
   "exercise_id": 51,
-  "type": "code_options"
+  "type": "code_options",
+  "author": "huanhuilong",
+  "notebook_enable": true
 }
\ No newline at end of file

data/1.python初阶/4.面向对象编程/5.抽象类/abstract.md

+# Python 抽象类创建
+
+使用 abc 库，创建抽象 BasePoint 类，创建 Point 子类，实现 dot 抽象方法，计算内积
+
+```python
+# -*- coding: UTF-8 -*-
+import abc
+
+# TODO(You): 请实现抽象类 BasePoint
+
+class Point(BasePoint):
+    def __init__(self, x, y, z) -> None:
+        super().__init__(x, y, z)
+
+    def dot(self, right):
+        return self.x*right.x+self.y*right.y+self.z*right.z
+
+if __name__ == '__main__':
+    p1 = Point(0, 1, 2)
+    p2 = Point(2, 4, 6)
+    assert p1.dot(p2) == 16
+    p1 = BasePoint(0, 1, 2)
+    p2 = BasePoint(2, 4, 6)
+    assert p1.dot(p2) is None
+```
+
+以下对 BasePoint 抽象类实现 **正确** 的代码是？
+
+## template
+
+```python
+import abc
+
+class BasePoint:
+    def __init__(self, x, y, z) -> None:
+        self.x = x
+        self.y = y
+        self.z = z
+
+    @abc.abstractmethod
+    def dot(self, right):
+        pass
+
+
+class Point(BasePoint):
+    def __init__(self, x, y, z) -> None:
+        super().__init__(x, y, z)
+
+    def dot(self, right):
+        return self.x*right.x+self.y*right.y+self.z*right.z
+
+
+if __name__ == '__main__':
+    p1 = Point(0, 1, 2)
+    p2 = Point(2, 4, 6)
+    assert p1.dot(p2) == 16
+    p1 = BasePoint(0, 1, 2)
+    p2 = BasePoint(2, 4, 6)
+    assert p1.dot(p2) is None
+```
+
+## 答案
+
+```python
+class BasePoint:
+    def __init__(self, x, y, z) -> None:
+        self.x = x
+        self.y = y
+        self.z = z
+
+    @abc.abstractmethod
+    def dot(self, right):
+        pass
+```
+
+## 选项
+
+### A
+
+```python
+class BasePoint:
+    def __init__(self, x, y, z) -> None:
+        self.x = x
+        self.y = y
+        self.z = z
+
+    @abstractmethod
+    def dot(self, right):
+        pass
+```
+
+### B
+
+```python
+class BasePoint:
+    def __init__(self, x, y, z) -> None:
+        self.x = x
+        self.y = y
+        self.z = z
+
+    def dot(self, right):
+        pass
+```
+
+### C
+
+```python
+class BasePoint:
+    def __init__(self, x, y, z) -> None:
+        self.x = x
+        self.y = y
+        self.z = z
+
+    @abc.abstractmethod
+    def dot(self, right):
+```

data/1.python初阶/4.面向对象编程/6.访问限制/access.json

 {
-  "one_line": {
-    "_func": [
-      "func"
-    ],
-    "__test": [
-      "test",
-      "_test",
-      "__test__"
-    ]
-  },
-  "source": "access.py",
+  "source": "access.md",
   "depends": [],
   "exercise_id": 55,
-  "type": "code_options"
+  "type": "code_options",
+  "author": "huanhuilong",
+  "notebook_enable": true
 }
\ No newline at end of file

data/1.python初阶/4.面向对象编程/6.访问限制/access.md

+# Python 访问控制
+
+分别编写类内部的私有方法，模块级别的私有方法
+
+请选出下列能**代码和注释一致**的代码。
+
+## template
+
+```python
+class Test:
+    def __init__(self) -> None:
+        pass
+
+    def test(self):
+        self.__test()
+
+    def __test(self):
+        '''类内部的私有方法'''
+        print("test")
+
+
+def _func():
+    '''模块级别的私有方法'''
+    print("file private")
+
+if __name__ == '__main__':
+    t = Test()
+    t.test()
+```
+
+## 答案
+
+```python
+class Test:
+    def test(self):
+        self.__test()
+
+    def __test(self):
+        '''类内部的私有方法'''
+        print("test")
+
+def _func():
+    '''模块级别的私有方法'''
+    print("file private")
+
+if __name__ == '__main__':
+    t = Test()
+    t.test()
+```
+
+## 选项
+
+### A
+
+```python
+class Test:
+    def test(self):
+        self._test()
+
+    def _test(self):
+        '''类内部的私有方法'''
+        print("test")
+
+def _func():
+    '''模块级别的私有方法'''
+    print("file private")
+
+if __name__ == '__main__':
+    t = Test()
+    t.test()
+```
+
+### B
+
+```python
+class Test:
+    def test(self):
+        self.__test__()
+
+    def __test__(self):
+        '''类内部的私有方法'''
+        print("test")
+
+def _func():
+    '''模块级别的私有方法'''
+    print("file private")
+
+if __name__ == '__main__':
+    t = Test()
+    t.test()
+```
+
+### C
+
+```python
+class Test:
+    def test(self):
+        self.__test()
+
+    def __test(self):
+        '''类内部的私有方法'''
+        print("test")
+
+def func():
+    '''模块级别的私有方法'''
+    print("file private")
+
+if __name__ == '__main__':
+    t = Test()
+    t.test()
+```

data/1.python初阶/4.面向对象编程/7.获取对象信息/object_meta.json

 {
-  "one_line": {
-    "hasattr": [
-      "has",
-      "attr",
-      "contains"
-    ],
-    "getattr": [
-      "get",
-      "attr"
-    ]
-  },
-  "source": "object_meta.py",
+  "source": "object_meta.md",
   "depends": [],
   "exercise_id": 53,
-  "type": "code_options"
+  "type": "code_options",
+  "author": "huanhuilong",
+  "notebook_enable": true
 }
\ No newline at end of file

data/1.python初阶/4.面向对象编程/7.获取对象信息/object_meta.md

+# Python 获取对象信息
+
+过滤列表里所有含有 'z' 属性的对象，打印他们的 'x'+'y'+'z' 的值
+
+```python
+# -*- coding: UTF-8 -*-
+class Point2D:
+    def __init__(self, x, y) -> None:
+        self.x = x
+        self.y = y
+
+class Point3D:
+    def __init__(self, x, y, z) -> None:
+        self.x = x
+        self.y = y
+        self.z = z
+
+class Vector2D:
+    def __init__(self, x, y) -> None:
+        self.x = x
+        self.y = y
+
+class Vector3D:
+    def __init__(self, x, y, z) -> None:
+        self.x = x
+        self.y = y
+        self.z = z
+
+def test():
+    points = [
+        Point2D(0, 1),
+        Point2D(0, 1),
+        Point3D(0, 1, 2),
+        Point3D(0, 1, 3),
+        Vector2D(0, 1),
+        Vector3D(0, 1, 4),
+    ]
+
+    z_objects = []
+    # TODO(You): 请在此过滤出含有'z'属性的对象，在过滤中打印出对应对象的'z'属性
+
+    for p in z_objects:
+        print('x+y+z:', p.x+p.y+p.z)
+
+if __name__ == '__main__':
+    test()
+```
+
+请选出下列能**正确**实现这一功能的选项。
+
+## template
+
+```python
+
+class Point2D:
+    def __init__(self, x, y) -> None:
+        self.x = x
+        self.y = y
+
+
+class Point3D:
+    def __init__(self, x, y, z) -> None:
+        self.x = x
+        self.y = y
+        self.z = z
+
+
+class Vector2D:
+    def __init__(self, x, y) -> None:
+        self.x = x
+        self.y = y
+
+
+class Vector3D:
+    def __init__(self, x, y, z) -> None:
+        self.x = x
+        self.y = y
+        self.z = z
+
+
+def test():
+    points = [
+        Point2D(0, 1),
+        Point2D(0, 1),
+        Point3D(0, 1, 2),
+        Point3D(0, 1, 3),
+        Vector2D(0, 1),
+        Vector3D(0, 1, 4),
+    ]
+
+    z_objects = []
+    for p in points:
+        if hasattr(p, 'z'):
+            z = getattr(p, 'z')
+            print('get z attr:', z)
+            z_objects.append(p)
+
+    for p in z_objects:
+        print('x+y+z:', p.x+p.y+p.z)
+
+if __name__ == '__main__':
+    test()
+```
+
+## 答案
+
+```python
+for p in points:
+    if hasattr(p, 'z'):
+        z = getattr(p, 'z')
+        print('get z attr:', z)
+        z_objects.append(p)
+```
+
+## 选项
+
+### A
+
+```python
+for p in points:
+    z = getattr(p, 'z')
+    print('get z attr:', z)
+    z_objects.append(p)
+```
+
+### B
+
+```python
+for p in points:
+    if not hasattr(p, 'z'):
+        z = getattr(p, 'z')
+        print('get z attr:', z)
+        z_objects.append(p)
+```
+
+### C
+
+```python
+for p in points:
+    if p.hasattr('z'):
+        z = p.getattr(p, 'z')
+        print('get z attr:', z)
+        z_objects.append(p)
+```

main.py

@@ -9,5 +9,5 @@ if __name__ == '__main__':
     # walker = TreeWalker("data", "python", "python")
     # walker.walk()
 
-    md = MDWalker('data/1.python初阶/2.基础语法')
+    md = MDWalker('data/1.python初阶/4.面向对象编程')
     md.walk()