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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 getStorageEngines(self):
 """Returns list of supported storage engines. @return: List of storage engine names. """

        cur = self._conn.cursor()
        cur.execute("""SHOW STORAGE ENGINES;""")
        rows = cur.fetchall()
        if rows:
            return [row[0].lower() for row in rows if row[1] in ['YES', 'DEFAULT']]
        else:
            return []