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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def fetch(url: str, **kwargs) -> Selector: """ Send HTTP request and parse it as a DOM tree. Args: url (str):
 The url of the site. Returns: Selector: allows you to select parts of HTML text using CSS or XPath expressions. """

    kwargs.setdefault('headers', DEFAULT_HEADERS)
    try:
        res = requests.get(url, **kwargs)
        res.raise_for_status()
    except requests.RequestException as e:
        print(e)
    else:
        html = res.text
        tree = Selector(text=html)
        return tree