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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_human_time(epoch_time):
 """Converts an epoch timestamp to human readable time. This essentially converts an output of get_current_epoch_time to an output of get_current_human_time Args: epoch_time: An integer representing an epoch timestamp in milliseconds. Returns: A time string representing the input time. None if input param is invalid. """

    if isinstance(epoch_time, int):
        try:
            d = datetime.datetime.fromtimestamp(epoch_time / 1000)
            return d.strftime("%m-%d-%Y %H:%M:%S ")
        except ValueError:
            return None