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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 register(self, path):
 """ Authorize a path for access by children. Repeat calls with the same path has no effect. :param str path: File path. """

        if path not in self._paths:
            LOG.debug('%r: registering %r', self, path)
            self._paths.add(path)