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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 size(self):
 """ Returns combined size in bytes for all repository files """


        size = 0
        try:
            tip = self.get_changeset()
            for topnode, dirs, files in tip.walk('/'):
                for f in files:
                    size += tip.get_file_size(f.path)
                for dir in dirs:
                    for f in files:
                        size += tip.get_file_size(f.path)

        except RepositoryError:
            pass
        return size