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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 intersection(self):
 """Compute the intersection with the given MOC. This command takes the name of a MOC file and forms the intersection of the running MOC with that file. :: pymoctool a.fits --intersection b.fits --output intersection.fits """


        if self.moc is None:
            raise CommandError('No MOC information present for intersection')

        filename = self.params.pop()
        self.moc = self.moc.intersection(MOC(filename=filename))