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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 __delete(self, key):
        ''' Delete file key from database
        '''
        with self.get_conn() as conn:
            try:
                c = conn.cursor()
                c.execute("DELETE FROM cache_entries WHERE key = ?", (key,))
                conn.commit()
            except:
                getLogger().exception("Cannot delete")
                return None