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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):
 """Update value based on the actual |calc_qg_v1| method. Required derived parameter: |H| Note that the value of parameter |lstream_derived.QM| is directly related to the value of parameter |HM| and indirectly related to all parameters values relevant for method |calc_qg_v1|. Hence the complete paramter (and sequence) requirements might differ for various application models. For examples, see the documentation on method ToDo. """

        mod = self.subpars.pars.model
        con = mod.parameters.control
        flu = mod.sequences.fluxes
        flu.h = con.hm
        mod.calc_qg()
        self(flu.qg)