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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_sets(self,directory):
 """Loads sets from set file and return as list of strings """

        # --- Read sets out of file
        _sets=[]
        try:
            fullfile=os.path.join(directory,SET_FILE)
            lsets=open(fullfile).readline().split(',')
            for tag in lsets:
                _sets.append(tag.strip())
        except:
            logger.error("No sets found in %s, FB needs an album name (%s)"\
                    %(directory,SET_FILE))
            sys.exit(1)

        return _sets