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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 headers_for_url(cls, url):
 """Return the headers only for the given URL as a dict"""

        response = cls.http_request(url, method='HEAD')
        if response.status != 200:
            cls.raise_http_error(response)

        return Resource.headers_as_dict(response)