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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 t_surf_parameter(self, num_frame, xax):
 """ Surface parameter evolution as a function of time or model. Parameters num_frame : integer Number of frame to plot this plot into. xax : string Either model or time to indicate what is to be used on the x-axis """


        pyl.figure(num_frame)

        if xax == 'time':
            xaxisarray = self.get('star_age')
        elif xax == 'model':
            xaxisarray = self.get('model_number')
        else:
            print('kippenhahn_error: invalid string for x-axis selction. needs to be "time" or "model"')


        logL    = self.get('log_L')
        logTeff    = self.get('log_Teff')

        pyl.plot(xaxisarray,logL,'-k',label='log L')
        pyl.plot(xaxisarray,logTeff,'-k',label='log Teff')
        pyl.ylabel('log L, log Teff')
        pyl.legend(loc=2)


        if xax == 'time':
            pyl.xlabel('t / yrs')
        elif xax == 'model':
            pyl.xlabel('model number')