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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 write(self, message, cur_time=None):
 """Write some text to the pusher. Args: message: a string to push for this file. cur_time: used for unit testing. override line timestamp. """

        if cur_time is None:
            cur_time = time.time()
        lines = self._line_buffer.add_string(message)
        for line in lines:
            #print('ts line', repr(line))
            timestamp = ''
            if self._prepend_timestamp:
                timestamp = datetime.datetime.utcfromtimestamp(
                    cur_time).isoformat() + ' '
            line = u'{}{}{}'.format(self._line_prepend, timestamp, line)
            self._fsapi.push(self._filename, line)