# Python Installation - macOS

## Check Current Version

```bash
python3 --version
```

If you see Python 3.11+, you're good to go! [← Back to main skill](../SKILL.md#step-2-create-virtual-environment)

---

## Installation Methods

### Option 1: Homebrew (Recommended)

**Why Homebrew:**
- Easy updates: `brew upgrade python@3.13`
- Manages dependencies automatically
- Industry standard on macOS

**Install Homebrew (if not installed):**
```bash
/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
```

**Install Python 3.13:**
```bash
brew install python@3.13
```

**Verify installation:**
```bash
python3.13 --version
# Or if it's the default:
python3 --version
```

**Add to PATH (if needed):**
```bash
echo 'export PATH="/opt/homebrew/bin:$PATH"' >> ~/.zshrc  # For M1/M2 Macs
echo 'export PATH="/usr/local/bin:$PATH"' >> ~/.zshrc     # For Intel Macs
source ~/.zshrc
```

---

### Option 2: Official Python Installer

**When to use:** You want specific Python version or don't use Homebrew

**Steps:**
1. Visit [python.org/downloads](https://www.python.org/downloads/)
2. Click "Download Python 3.13.x" button
3. Open downloaded `.pkg` file
4. Follow installation wizard
5. Restart Terminal

**Verify:**
```bash
python3 --version
```

**Add to PATH (if needed):**
```bash
echo 'export PATH="/Library/Frameworks/Python.framework/Versions/3.13/bin:$PATH"' >> ~/.zshrc
source ~/.zshrc
```

---

### Option 3: pyenv (Multiple Python Versions)

**Why pyenv:**
- Manage multiple Python versions side-by-side
- Easy switching between projects
- Preferred by professional developers

**Install pyenv:**
```bash
brew install pyenv
```

**Install Python 3.13:**
```bash
pyenv install 3.13.0
```

**Set as global default:**
```bash
pyenv global 3.13.0
```

**Or set for specific project:**
```bash
cd /path/to/project
pyenv local 3.13.0
```

**Configure shell (add to ~/.zshrc):**
```bash
export PYENV_ROOT="$HOME/.pyenv"
export PATH="$PYENV_ROOT/bin:$PATH"
eval "$(pyenv init --path)"
eval "$(pyenv init -)"
```

**Reload shell:**
```bash
source ~/.zshrc
```

**Verify:**
```bash
python --version  # Should show 3.13.0
```

---

## Troubleshooting

### Issue: `command not found: python3`

**After Homebrew install:**
```bash
brew link python@3.13
```

**Check where Python is:**
```bash
which python3
brew --prefix python@3.13
```

### Issue: Multiple Python versions conflict

**List all Python installations:**
```bash
which -a python3
ls -l /usr/local/bin/python*
```

**Use specific version:**
```bash
python3.13 -m venv venv  # Force Python 3.13
```

### Issue: SSL certificate errors

**Install certificates:**
```bash
/Applications/Python\ 3.13/Install\ Certificates.command
```

Or via Homebrew:
```bash
brew install openssl
```

### Issue: Xcode Command Line Tools needed

**Install:**
```bash
xcode-select --install
```

---

## Verification Checklist

- [ ] `python3 --version` shows 3.11+
- [ ] `which python3` shows installation path
- [ ] `python3 -m pip --version` works
- [ ] `python3 -m venv test_venv` creates test environment
- [ ] Can activate test venv: `source test_venv/bin/activate`

**Clean up test:**
```bash
rm -rf test_venv
```

---

[← Back to django-project-setup](../SKILL.md)