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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 _get_platform(self):
 """Get the platform name The platform is not specified explicitly in JMA HRIT files. For segmented data it is not even specified in the filename. But it can be derived indirectly from the projection name: GEOS(140.00):
 MTSAT-1R GEOS(140.70):
 Himawari-8 GEOS(145.00):
 MTSAT-2 See [MTSAT], section 3.1. Unfortunately Himawari-8 and 9 are not distinguishable using that method at the moment. From [HIMAWARI]: "HRIT/LRIT files have the same file naming convention in the same format in Himawari-8 and Himawari-9, so there is no particular difference." TODO: Find another way to distinguish Himawari-8 and 9. References: [MTSAT] http://www.data.jma.go.jp/mscweb/notice/Himawari7_e.html [HIMAWARI] http://www.data.jma.go.jp/mscweb/en/himawari89/space_segment/sample_hrit.html """

        try:
            return PLATFORMS[self.projection_name]
        except KeyError:
            logger.error('Unable to determine platform: Unknown projection '
                         'name "{}"'.format(self.projection_name))
            return UNKNOWN_PLATFORM