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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 _load_megapixels(self,directory):
 """Opens megapixel file, if contains '3.5' for instance, will scale all uploaded photos in directory this this size, the original photo is untouched. Returns None if file not found """

        #FIXME: should check if DB tracking file before using it

        fullfile=os.path.join(directory,MEGAPIXEL_FILE)
        try:
            mp=float(open(fullfile).readline())
            logger.debug("_load_megapixel: MP from file is %f",mp)
        except:
            logger.warning("Couldn't open image size file in %s, not scaling images"\
                    %(directory))
            return None

        return mp