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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 clampings_iter(self, cues=None):
 """ Iterates over all possible clampings of this experimental setup Parameters cues : Optional[iterable] If given, restricts clampings over given species names Yields ------ caspo.core.clamping.Clamping The next clamping with respect to the experimental setup """

        s = cues or list(self.stimuli + self.inhibitors)
        clampings = it.chain.from_iterable(it.combinations(s, r) for r in xrange(len(s) + 1))

        literals_tpl = {}
        for stimulus in self.stimuli:
            literals_tpl[stimulus] = -1

        for c in clampings:
            literals = literals_tpl.copy()
            for cues in c:
                if cues in self.stimuli:
                    literals[cues] = 1
                else:
                    literals[cues] = -1

            yield Clamping(literals.iteritems())