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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 format_as_utc(self, value):
 """Format UTC times."""

        if isinstance(value, datetime.datetime):
            if value.tzinfo is not None:
                value = value.astimezone(pytz.UTC)
            value = value.replace(microsecond=0)
        return value.isoformat().replace('+00:00', 'Z')