Doesn't work with bun.js because require.extensions[template.defaults.extname] = extension; looks like it's not supported
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Hi no speak chinese :)

Apparently this line of code is deprecated.  It doesn't work with Bun.js.  Is there a workaround?  Thank you! This is a great library

```
const template = require('./lib/index');
const extension = require('./lib/extension');

template.extension = extension;
>>> require.extensions[template.defaults.extname] = extension;

module.exports = template;
```

TypeError: undefined is not an object (evaluating 'import.meta.require.extensions[template.defaults.extname] = extension')
