from random import randint

class Die():

def _init_(self,num_sides=6):
    self.num_sides=num_sides
def roll(self):
    return randint(1,self.num_sides)

die=Die()
results=[]
for roll_num in range(1,100):

result=die.roll()
results.append(result)

print(results)

报错：
raceback (most recent call last):
File "D:/python_work/die_visual.py", line 11, in <module>

result=die.roll()

File "D:/python_work/die_visual.py", line 6, in roll

return randint(1,self.num_sides)

AttributeError: 'Die' object has no attribute 'num_sides'

Process finished with exit code 1