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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 post(self, value, addend, unit):
 """A date adder endpoint."""

        value = value or dt.datetime.utcnow()
        if unit == "minutes":
            delta = dt.timedelta(minutes=addend)
        else:
            delta = dt.timedelta(days=addend)
        result = value + delta
        return {"result": result.isoformat()}