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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 log(self, argin):
 """Log a command for the SDP STango ubsystem devices."""

        #
        # Tango Manual Appendix 9 gives the format
        # argin[0] = millisecond Unix timestamp
        # argin[1] = log level
        # argin[2] = the source log device name
        # argin[3] = the log message
        # argin[4] = Not used - reserved
        # argin[5] = thread identifier of originating message

        tm = datetime.datetime.fromtimestamp(float(argin[0])/1000.)
        fmt = "%Y-%m-%d %H:%M:%S"
        message = "TANGO Log message - {} - {} {} {}".format(
            tm.strftime(fmt), argin[1], argin[2], argin[3])
        LOG.info(message)