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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 is_available(self, fname):
 """ Check availability of a remote file without downloading it. Use this method when working with large files to check if they are available for download. Parameters fname : str The file name (relative to the *base_url* of the remote data storage) to fetch from the local storage. Returns ------- status : bool True if the file is available for download. False otherwise. """

        self._assert_file_in_registry(fname)
        source = self.get_url(fname)
        response = requests.head(source, allow_redirects=True)
        return bool(response.status_code == 200)