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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(self, key):
 """ Fetch entry from database. """

        c = self.conn.cursor()
        for row in c.execute("SELECT key, nonce, key_handle, aead, oath_C, oath_T FROM oath WHERE key = ?", (key,)):
            return ValOathEntry(row)
        raise Exception("OATH token for '%s' not found in database (%s)" % (key, self.filename))