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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 _get_digest(self, info):
 """ Get a digest from a dictionary by looking at keys of the form 'algo_digest'. Returns a 2-tuple (algo, digest) if found, else None. Currently looks only for SHA256, then MD5. """

        result = None
        for algo in ('sha256', 'md5'):
            key = '%s_digest' % algo
            if key in info:
                result = (algo, info[key])
                break
        return result