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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 set_projection(self, val):
 """Set the projection of the given axis in this coordinate. The known projections are SIN, ZEA, TAN, NCP, AIT, ZEA """

        knownproj = ["SIN", "ZEA", "TAN", "NCP", "AIT", "ZEA"]  # etc
        assert val.upper() in knownproj
        self._coord["projection"] = val.upper()