def METHOD_NAME(self, sep: str = "\n"):
    res = []
    def append(s: str = None):
        if s is not None:
            res.append(s)
        res.append(sep)
    append("Pcie profiling result:")
    append("time of data transmission (CPU -> GPU): {}".format(_format_time(self.h2d_time)))
    append("number of transmission (CPU -> GPU): {}".format(self.h2d_count))
    append("time of data transmission (GPU -> CPU): {}".format(_format_time(self.d2h_time)))
    append("number of transmission (GPU -> CPU): {}".format(self.d2h_count))
    append("Possible data transmission events in PCIE:")
    separation = '-' * 62
    row_format = '{:^10}' + '{:^12}' + '{:^16}' + '{:^12}' * 2
    append(separation)
    append(row_format.format('Location', 'GPU time', 'Trans volume', 'Bandwidth', 'Num of calls'))
    append(separation)
    show_list = sorted(self.ops_record.items(), key=lambda kv: -kv[1].cuda_time)
    for location, event in show_list:
        append(location)
        append(
            row_format.format('', _format_time(event.cuda_time), _format_memory(event.pcie_vol),
                              _format_bandwidth(event.pcie_vol, event.cuda_time), event.count))
        append()
    return ''.join(res)