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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 assertit(self):
 """Assert the fact within the CLIPS environment."""

        if self.asserted:
            raise RuntimeError("Fact already asserted")

        lib.EnvAssignFactSlotDefaults(self._env, self._fact)

        if lib.EnvAssert(self._env, self._fact) == ffi.NULL:
            raise CLIPSError(self._env)