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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_qm_v1(self):
 """Calculate the discharge of the main channel after Manning-Strickler. Required control parameters: |EKM| |SKM| |Gef| Required flux sequence: |AM| |UM| Calculated flux sequence: |lstream_fluxes.QM| Examples: For appropriate strictly positive values: qm(17.053102) For zero or negative values of the flown through surface or the wetted perimeter: qm(0.0) qm(0.0) """

    con = self.parameters.control.fastaccess
    flu = self.sequences.fluxes.fastaccess
    if (flu.am > 0.) and (flu.um > 0.):
        flu.qm = con.ekm*con.skm*flu.am**(5./3.)/flu.um**(2./3.)*con.gef**.5
    else:
        flu.qm = 0.