Python Development Environment Cheatsheet

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# Install Python
sudo apt update
sudo apt install python3
sudo apt install python3-pip

# Install virtual environment
sudo apt install python3-venv

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# Using Homebrew
brew install python3

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winget install Python.3

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# Create virtual environment
python3 -m venv myenv

# Activate virtual environment
source myenv/bin/activate      # Linux/macOS
myenv\Scripts\activate.bat     # Windows CMD
myenv\Scripts\Activate.ps1     # Windows PowerShell

# Deactivate
deactivate

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# Install packages
pip install package_name
pip install package_name==1.2.3  # Specific version

# Install from requirements.txt
pip install -r requirements.txt

# Generate requirements.txt
pip freeze > requirements.txt

# Upgrade pip
python -m pip install --upgrade pip

# List installed packages
pip list

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# Create environment
conda create --name myenv python=3.9

# Activate environment
conda activate myenv

# Deactivate environment
conda deactivate

# List environments
conda env list

# Install packages
conda install package_name

# Update conda
conda update conda

# List installed packages
conda list

# Remove environment
conda env remove --name myenv

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# Export environment
conda env export > environment.yml

# Create environment from file
conda env create -f environment.yml

# Clean unused packages and caches
conda clean --all

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project_name/
├── README.md
├── requirements.txt
├── setup.py
├── .gitignore
├── .env
├── docs/
├── tests/
│   ├── __init__.py
│   └── test_main.py
└── project_name/
    ├── __init__.py
    ├── main.py
    └── utils/
        └── __init__.py

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# Install formatters
pip install black
pip install isort

# Format code
black .
isort .

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# Install linters
pip install flake8
pip install pylint

# Run linters
flake8 .
pylint your_module.py

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# Install mypy
pip install mypy

# Run type checking
mypy your_module.py

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# Install pytest
pip install pytest
pip install pytest-cov

# Run tests
pytest
pytest --cov=your_module  # With coverage

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# Using python-dotenv
from dotenv import load_dotenv
import os

load_dotenv()
api_key = os.getenv('API_KEY')

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import logging

# Configure logging
logging.basicConfig(
    level=logging.INFO,
    format='%(asctime)s - %(name)s - %(levelname)s - %(message)s'
)

logger = logging.getLogger(__name__)
logger.info('This is an info message')

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try:
    # Risky operation
    result = some_function()
except ValueError as e:
    logger.error(f"Value error occurred: {e}")
except Exception as e:
    logger.error(f"Unexpected error: {e}")
else:
    # Run if no exception
    process_result(result)
finally:
    # Always run
    cleanup()