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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 blob_exists(self, table, digest):
 """ Returns true if the blob with the given digest exists under the given table. """

        response = self._request('HEAD', _blob_path(table, digest))
        if response.status == 200:
            return True
        elif response.status == 404:
            return False
        _raise_for_status(response)