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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 add_threat_list(self, threat_list):
 """Add threat list entry if it does not exist."""

        q = '''INSERT OR IGNORE INTO threat_list
                    (threat_type, platform_type, threat_entry_type, timestamp)
                VALUES
                    (?, ?, ?, current_timestamp)
        '''
        params = [threat_list.threat_type, threat_list.platform_type, threat_list.threat_entry_type]
        with self.get_cursor() as dbc:
            dbc.execute(q, params)