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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 trim(self, lower=None, upper=None):
 """Trim negative value whenever there is no internal lake within the respective subbasin. lz(-1.0) lz(0.0) lz(1.0) """

        if upper is None:
            control = self.subseqs.seqs.model.parameters.control
            if not any(control.zonetype.values == ILAKE):
                lower = 0.
        sequencetools.StateSequence.trim(self, lower, upper)