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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 with_url(self, url):
 """Sets the request's URL and returns the request itself. Automatically sets the Host header according to the URL. Keyword arguments: url -- a string representing the URL the set for the request """

        self.url = URL(url)
        self.header["Host"] = self.url.host
        return self