A problem with child class

[gontajones]

You can add the speed at the __init__() or maybe just use it in the run().

def __init__(self, name, age):
        self.name = name
        self.age = age
        self.speed = 'Normal'

Then..

class Bulldog(Dog):
    def run(self, speed):
        self.speed = speed
        return f'{self.name} runs {self.speed}'

Or

class RussellTerrier(Dog):
    def run(self, speed):
        return f'{self.name} runs {speed}'