请给出本科阶段学习Python的类的相关知识点，并举例

本科阶段学习Python的类的相关知识点包括：

1. 类的定义和实例化：学习如何定义类和创建类的实例对象。
示例代码：

   class Person:
       def __init__(self, name, age):
           self.name = name
           self.age = age

       def say_hello(self):
           print("Hello, my name is {} and I am {} years old.".format(self.name, self.age))

   person1 = Person("Alice", 25)
   person2 = Person("Bob", 30)

   person1.say_hello()  # 输出 "Hello, my name is Alice and I am 25 years old."
   person2.say_hello()  # 输出 "Hello, my name is Bob and I am 30 years old."

2. 类的继承：学习如何使用继承来创建一个新的类，该类从另一个类继承属性和方法。
示例代码：

   class Student(Person):
       def __init__(self, name, age, major):
           super().__init__(name, age)
           self.major = major

       def say_hello(self):
           super().say_hello()
           print("I am studying {}.".format(self.major))

   student1 = Student("Charlie", 20, "Computer Science")
   student1.say_hello()  # 输出 "Hello, my name is Charlie and I am 20 years old. I am studying Computer Science."

3. 类的属性和方法：学习如何在类中定义属性和方法，并使用它们来操作类的实例对象。
示例代码：

   class Rectangle:
       def __init__(self, width, height):
           self.width = width
           self.height = height

       def area(self):
           return self.width * self.height

       def perimeter(self):
           return 2 * (self.width + self.height)

   rect1 = Rectangle(5, 10)
   print(rect1.area())  # 输出 50
   print(rect1.perimeter())  # 输出 30

4. 类的特殊方法：学习如何定义特殊方法，例如 `__str__` 和 `__eq__`，用于自定义类的字符串表示和相等性比较。
示例代码：

   class Point:
       def __init__(self, x, y):
           self.x = x
           self.y = y

       def __str__(self):
           return "({}, {})".format(self.x, self.y)

       def __eq__(self, other):
           return self.x == other.x and self.y == other.y

   point1 = Point(1, 2)
   point2 = Point(3, 4)
   point3 = Point(1, 2)

   print(point1)  # 输出 "(1, 2)"
   print(point1 == point2)  # 输出 False
   print(point1 == point3)  # 输出 True