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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 asserted(self):
 """True if the fact has been asserted within CLIPS."""

        # https://sourceforge.net/p/clipsrules/discussion/776945/thread/4f04bb9e/
        if self.index == 0:
            return False

        return bool(lib.EnvFactExistp(self._env, self._fact))