python-patternslisted
Install: claude install-skill Jartan-LLC/grimoire
# Python Development Patterns
Idiomatic Python patterns and best practices for building robust, efficient, and maintainable applications.
## Core Concepts
### 1. Readability Counts
Python prioritizes readability. Code should be obvious and easy to understand.
```python
# Good: Clear and readable
def get_active_users(users: list[User]) -> list[User]:
"""Return only active users from the provided list."""
return [user for user in users if user.is_active]
# Bad: Clever but confusing
def get_active_users(u):
return [x for x in u if x.a]
```
### 2. Explicit is Better Than Implicit
Avoid magic; be clear about what your code does.
```python
# Good: Explicit configuration
import logging
logging.basicConfig(
level=logging.INFO,
format='%(asctime)s - %(name)s - %(levelname)s - %(message)s'
)
# Bad: Hidden side effects
import some_module
some_module.setup() # What does this do?
```
### 3. EAFP - Easier to Ask Forgiveness Than Permission
Python prefers exception handling over checking conditions.
```python
# Good: EAFP style
def get_value(dictionary: dict, key: str) -> Any:
try:
return dictionary[key]
except KeyError:
return default_value
# Bad: LBYL (Look Before You Leap) style
def get_value(dictionary: dict, key: str) -> Any:
if key in dictionary:
return dictionary[key]
else:
return default_value
```
## Type Hints
### Basic Type Annotations
```python
from typing import Optional, List, Dict, Any
def