### Install valtio and valtio-reactive

Source: https://github.com/valtiojs/valtio-reactive/blob/main/README.md

Installs the necessary packages for using valtio-reactive, including Valtio itself and the valtio-reactive library.

```bash
npm install valtio valtio-reactive
```

--------------------------------

### Valtio Reactive Usage Example

Source: https://github.com/valtiojs/valtio-reactive/blob/main/README.md

Demonstrates how to use valtio-reactive with Valtio. It shows creating a reactive state, defining a computed property that depends on the state, and setting up an effect to react to changes in the computed property. Updates are batched for efficiency.

```javascript
import { proxy } from 'valtio/vanilla';
import { batch, computed, effect } from 'valtio-reactive';

const state = proxy({ count: 1 });

const derived = computed({
  double: () => state.count * 2,
});

effect(() => {
  console.log('double count:', derived.double);
});

setInterval(() => {
  batch(() => {
    state.count++;
    state.count++;
  });
}, 1000);
```

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