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Python Object-Oriented Python (retired) Inheritance Subclasses

Aaron Brown
Aaron Brown
2,551 Points
Posted by Aaron Brown
Aaron Brown
2,551 Points

Terminal output is different from Workspaces output

Hello!

I am working on my Terminal opposed to the workspaces, and I should note that I am using Python3.

When Kenneth inputs azog = monster.Goblin() he gets assignment of azog to the Goblin subclass of Monster. However, I get:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'monster' is not defined

But when I leave out '.monster' and just insert: azog = Goblin , the assignment works just fine and I get:

<class '__main__.Goblin'>

What's going on? Here's my code just to make sure I didn't make some mistake somewhere.

import random

COLORS = ['yellow', 'red', 'blue', 'green']


class Monster:
    min_hit_points = 1
    max_hit_points = 1
    min_experience = 1
    max_experience = 1
    weapon = 'sword'
    sound = 'roar'

    def __init__(self, **kwargs):
        self.hit_points = random.randint(self.min_hit_points, self.max_hit_points)
        self.experience = random.randint(self.min_experience, self.max_experience)
        self.color = random.choice(COLORS)

        for key, value in kwargs.items():
            setattr(self, key, value)

    def battlecry(self):
        return self.sound.upper()

# passing the Monster class inside of parentheses, tells Python that Goblin is a subclass of monster, which means Goblin has all the attrs of Monsters unless modified within Goblin
class Goblin(Monster): 
    max_hit_points = 3
    max_experience = 2
    sound = 'squeak'

class Troll(Monster):
    min_hit_points = 3
    max_hit_points = 5
    min_experience = 2
    max_experience = 6
    sound = 'growl'

class Dragon(Monster):
    min_hit_points = 5
    max_hit_points = 10
    min_experience = 6
    max_experience = 10
    sound = 'raaaaaaaaaaaar'

Thank you! I look forward to any input, and please let me know if this is not clear.

Best, Aaron

1 Answer

Trevor Skelton
Trevor Skelton
1,101 Points
Trevor Skelton
Trevor Skelton
1,101 Points

In your post you say Kenneth typed 'azog = monster.Goblin()'. I watched the video and saw him type 'azog = Goblin()'. If you use 'from monster import Goblin'. 'azog = Goblin()' should work. The reason you would use monster.Goblin() was to get the class out of the monster file by just typing 'import monster'. The way you import changes the line. e.g.

from monster import Goblin azog = Goblin()

or

import monster azog = monster.Goblin()

Aaron Brown
Aaron Brown
2,551 Points
Aaron Brown
Aaron Brown
2,551 Points

Thanks, Trevor!

Actually. I ended up figuring this out a few minutes after I posted. Why does it call differently depending on how I import? I feel this is probably an important concept to understand when moving forward with projects.

Aaron

Trevor Skelton
Trevor Skelton
1,101 Points
Trevor Skelton
Trevor Skelton
1,101 Points

I found the best answer I could find for you. I tried to think of a way to explain it, but this guy has a better explanation. I hope this helps with your question.

Link is here

Aaron Brown
Aaron Brown
2,551 Points
Aaron Brown
Aaron Brown
2,551 Points

Hey, Trevor! Thanks for that link. It was incredibly helpful.