classes

class Student:
    def __init__(self, name="name", mark=0, age=None):
       self.name = name
       self.mark = mark
       self.age = age
    
    def mark5(self):
        if self.mark >= 8:
            m = 5
        if self.mark in [6, 7]:
            m = 4
        if self.mark in [4, 5]:
            m = 3
        if self.mark < 4:
            m = 2
        return m
        
       
 st = Student()
 
 st.name
 st.mark
 st.age
 
 ann = Student('Ann', 7, 19)