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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 update(self):
 """Determine the number of response functions. nmb(2) Note that updating parameter `nmb` sets the shape of the flux sequences |QPIn|, |QPOut|, |QMA|, and |QAR| automatically. qpin(nan, nan) qpout(nan, nan) qma(nan, nan) qar(nan, nan) """

        pars = self.subpars.pars
        responses = pars.control.responses
        fluxes = pars.model.sequences.fluxes
        self(len(responses))
        fluxes.qpin.shape = self.value
        fluxes.qpout.shape = self.value
        fluxes.qma.shape = self.value
        fluxes.qar.shape = self.value