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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 _readable_flags(transport):
 """Method that turns bit flags into a human readable list Args: transport (dict):
 transport info, specifically needs a 'flags' key with bit_flags Returns: """

        if 'flags' not in transport:
            return None
        _flag_list = []
        flags = transport['flags']
        if flags & dpkt.tcp.TH_SYN:
            if flags & dpkt.tcp.TH_ACK:
                _flag_list.append('syn_ack')
            else:
                _flag_list.append('syn')
        elif flags & dpkt.tcp.TH_FIN:
            if flags & dpkt.tcp.TH_ACK:
                _flag_list.append('fin_ack')
            else:
                _flag_list.append('fin')
        elif flags & dpkt.tcp.TH_RST:
            _flag_list.append('rst')
        elif flags & dpkt.tcp.TH_PUSH:
            _flag_list.append('psh')
        return _flag_list