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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_bowa_v1(self):
 """Update soil moisture and correct fluxes if necessary. Required control parameters: |NHRU| |Lnk| Required flux sequence: |WaDa| Updated state sequence: |BoWa| Required (and eventually corrected) flux sequences: |EvB| |QBB| |QIB1| |QIB2| |QDB| Basic equations: :math:`\\frac{dBoWa}{dt} = WaDa - EvB - QBB - QIB1 - QIB2 - QDB` :math:`BoWa \\geq 0` Examples: For water areas (|FLUSS| and |SEE|) and sealed areas (|VERS|), soil moisture |BoWa| is simply set to zero and no flux correction are performed (see the first three HRUs). No principal distinction is made between the remaining land use classes (arable land |ACKER| has been selected for the last four HRUs arbitrarily):
 bowa(0.0, 0.0, 0.0, 3.0, 1.5, 0.0, 0.0) evb(1.0, 1.0, 1.0, 0.0, 0.1, 0.2, 0.2) qbb(1.0, 1.0, 1.0, 0.0, 0.2, 0.4, 0.4) qib1(1.0, 1.0, 1.0, 0.0, 0.3, 0.6, 0.6) qib2(1.0, 1.0, 1.0, 0.0, 0.4, 0.8, 0.8) qdb(1.0, 1.0, 1.0, 0.0, 0.5, 1.0, 1.0) For the seventh HRU, the original total loss terms would result in a negative soil moisture value. Hence it is reduced to the total loss term of the sixt HRU, which results exactly in a complete emptying of the soil storage. """

    con = self.parameters.control.fastaccess
    flu = self.sequences.fluxes.fastaccess
    sta = self.sequences.states.fastaccess
    aid = self.sequences.aides.fastaccess
    for k in range(con.nhru):
        if con.lnk[k] in (VERS, WASSER, FLUSS, SEE):
            sta.bowa[k] = 0.
        else:
            aid.bvl[k] = (
                flu.evb[k]+flu.qbb[k]+flu.qib1[k]+flu.qib2[k]+flu.qdb[k])
            aid.mvl[k] = sta.bowa[k]+flu.wada[k]
            if aid.bvl[k] > aid.mvl[k]:
                aid.rvl[k] = aid.mvl[k]/aid.bvl[k]
                flu.evb[k] *= aid.rvl[k]
                flu.qbb[k] *= aid.rvl[k]
                flu.qib1[k] *= aid.rvl[k]
                flu.qib2[k] *= aid.rvl[k]
                flu.qdb[k] *= aid.rvl[k]
                sta.bowa[k] = 0.
            else:
                sta.bowa[k] = aid.mvl[k]-aid.bvl[k]