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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 calc_hmin_qmin_hmax_qmax_v1(self):
 """Determine an starting interval for iteration methods as the one implemented in method |calc_h_v1|. The resulting interval is determined in a manner, that on the one hand :math:`Qmin \\leq QRef \\leq Qmax` is fulfilled and on the other hand the results of method |calc_qg_v1| are continuous for :math:`Hmin \\leq H \\leq Hmax`. Required control parameter: |HM| Required derived parameters: |HV| |lstream_derived.QM| |lstream_derived.QV| Required flux sequence: |QRef| Calculated aide sequences: |HMin| |HMax| |QMin| |QMax| Besides the mentioned required parameters and sequences, those of the actual method for calculating the discharge of the total cross section might be required. This is the case whenever water flows on both outer embankments. In such occasions no previously determined upper boundary values are available and method |calc_hmin_qmin_hmax_qmax_v1| needs to increase the value of :math:`HMax` successively until the condition :math:`QG \\leq QMax` is met. """

    con = self.parameters.control.fastaccess
    der = self.parameters.derived.fastaccess
    flu = self.sequences.fluxes.fastaccess
    aid = self.sequences.aides.fastaccess
    if flu.qref <= der.qm:
        aid.hmin = 0.
        aid.qmin = 0.
        aid.hmax = con.hm
        aid.qmax = der.qm
    elif flu.qref <= min(der.qv[0], der.qv[1]):
        aid.hmin = con.hm
        aid.qmin = der.qm
        aid.hmax = con.hm+min(der.hv[0], der.hv[1])
        aid.qmax = min(der.qv[0], der.qv[1])
    elif flu.qref < max(der.qv[0], der.qv[1]):
        aid.hmin = con.hm+min(der.hv[0], der.hv[1])
        aid.qmin = min(der.qv[0], der.qv[1])
        aid.hmax = con.hm+max(der.hv[0], der.hv[1])
        aid.qmax = max(der.qv[0], der.qv[1])
    else:
        flu.h = con.hm+max(der.hv[0], der.hv[1])
        aid.hmin = flu.h
        aid.qmin = flu.qg
        while True:
            flu.h *= 2.
            self.calc_qg()
            if flu.qg < flu.qref:
                aid.hmin = flu.h
                aid.qmin = flu.qg
            else:
                aid.hmax = flu.h
                aid.qmax = flu.qg
                break