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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_time_step_first(self):
 """ Compute the first time step and save to ``self.h`` Returns ------- None """

        system = self.system
        config = self.config

        if not system.dae.n:
            freq = 1.0
        elif system.dae.n == 1:
            B = matrix(system.dae.Gx)
            self.solver.linsolve(system.dae.Gy, B)
            As = system.dae.Fx - system.dae.Fy * B
            freq = abs(As[0, 0])
        else:
            freq = 20.0

        if freq > system.freq:
            freq = float(system.freq)

        tspan = abs(config.tf - config.t0)
        tcycle = 1 / freq
        config.deltatmax = min(5 * tcycle, tspan / 100.0)
        config.deltat = min(tcycle, tspan / 100.0)
        config.deltatmin = min(tcycle / 64, config.deltatmax / 20)

        if config.fixt:
            if config.tstep <= 0:
                logger.warning('Fixed time step is negative or zero')
                logger.warning('Switching to automatic time step')
                config.fixt = False
            else:
                config.deltat = config.tstep
                if config.tstep < config.deltatmin:
                    logger.warning(
                        'Fixed time step is below the estimated minimum')

        self.h = config.deltat