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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 epoch_to_log_line_timestamp(epoch_time, time_zone=None):
 """Converts an epoch timestamp in ms to log line timestamp format, which is readible for humans. Args: epoch_time: integer, an epoch timestamp in ms. time_zone: instance of tzinfo, time zone information. Using pytz rather than python 3.2 time_zone implementation for python 2 compatibility reasons. Returns: A string that is the corresponding timestamp in log line timestamp format. """

    s, ms = divmod(epoch_time, 1000)
    d = datetime.datetime.fromtimestamp(s, tz=time_zone)
    return d.strftime('%m-%d %H:%M:%S.') + str(ms)