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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_q1_lz_v1(self):
 """Calculate the slow response of the lower zone layer. Required control parameters: |K4| |Gamma| Calculated fluxes sequence: |Q1| Updated state sequence: |LZ| Basic equations: :math:`\\frac{dLZ}{dt} = -Q1` \n :math:`Q1 = \\Bigl \\lbrace { {K4 \\cdot LZ^{1+Gamma} \\ | \\ LZ > 0} \\atop {0 \\ | \\ LZ\\leq 0} }` Examples: q1(0.0) lz(-2.0) q1(0.0) lz(0.0) q1(0.2) lz(1.8) q1(0.4) lz(1.6) Note that the assumed length of the simulation step is only a half day. Hence the effective value of the storage coefficient is not 0.2 but 0.1: k4(0.2) 0.1 """

    con = self.parameters.control.fastaccess
    flu = self.sequences.fluxes.fastaccess
    sta = self.sequences.states.fastaccess
    if sta.lz > 0.:
        flu.q1 = con.k4*sta.lz**(1.+con.gamma)
    else:
        flu.q1 = 0.
    sta.lz -= flu.q1