Tirsvad
1026c7f32a
Plan waived by the user in chat for this request: a demo of a Python class, no planning or tests.
56 lines
1.1 KiB
Markdown
56 lines
1.1 KiB
Markdown
# 017-followers
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Day 17 of the Udemy *100 Days of Code* course: a small example of how to
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define and use a Python class.
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This is a demonstration only. It has no plan, no tests and no dependencies.
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## What it shows
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The `User` class in [src/main.py](src/main.py) demonstrates:
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- a constructor (`__init__`) that sets attributes with default values
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- instance attributes (`id`, `username`, `followers`, `following`)
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- a method (`follow`) that changes the state of two objects at once
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```python
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class User:
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def __init__(self, user_id, username):
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self.id = user_id
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self.username = username
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self.followers = 0
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self.following = 0
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def follow(self, user):
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user.followers += 1
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self.following += 1
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```
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When `user_1.follow(user_2)` runs, `user_1.following` goes up by one and
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`user_2.followers` goes up by one.
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## Run it
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```bash
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python src/main.py
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```
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Expected output:
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```text
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0
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1
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1
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0
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```
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The four lines are `user_1.followers`, `user_1.following`,
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`user_2.followers` and `user_2.following`.
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## Layout
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| Path | Purpose |
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| --- | --- |
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| `src/main.py` | The `User` class and the demo that uses it |
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