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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_lat(self, lat):
        ''' Format latitude to fit the image name '''

        if self.ppd in [4, 8, 16, 32, 64]:
            latcenter = '000N'
        elif self.ppd in [128]:
            if lat < 0:
                latcenter = '450S'
            else:
                latcenter = '450N'

        return latcenter