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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_epc_v1(self):
 """Apply the evaporation correction factors and adjust evaporation to the altitude of the individual zones. Calculate the areal mean of (uncorrected) potential evaporation for the subbasin, adjust it to the individual zones in accordance with their heights and perform some corrections, among which one depends on the actual precipitation. Required control parameters: |NmbZones| |ECorr| |ECAlt| |ZoneZ| |ZRelE| |EPF| Required flux sequences: |EP| |PC| Calculated flux sequences: |EPC| Basic equation: :math:`EPC = EP \\cdot ECorr \\cdot (1+ECAlt \\cdot (ZoneZ-ZRelE)) \\cdot exp(-EPF \\cdot PC)` Examples: Four zones are at an elevation of 200 m. A (uncorrected) potential evaporation value of 2 mm and a (corrected) precipitation value of 5 mm have been determined for each zone beforehand: The first three zones illustrate the individual evaporation corrections due to the general evaporation correction factor (|ECorr|, first zone), the altitude correction factor (|ECAlt|, second zone), the precipitation related correction factor (|EPF|, third zone). The fourth zone illustrates the interaction between all corrections: epc(2.6, 1.8, 1.4, 1.638) To prevent from calculating negative evaporation values when too large values for parameter |ECAlt| are set, a truncation is performed: epc(0.0, 0.0, 0.0, 0.0) """

    con = self.parameters.control.fastaccess
    flu = self.sequences.fluxes.fastaccess
    for k in range(con.nmbzones):
        flu.epc[k] = (flu.ep[k]*con.ecorr[k] *
                      (1. - con.ecalt[k]*(con.zonez[k]-con.zrele)))
        if flu.epc[k] <= 0.:
            flu.epc[k] = 0.
        else:
            flu.epc[k] *= modelutils.exp(-con.epf[k]*flu.pc[k])