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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 plot_prof_sparse(self, mod, species, xlim1, xlim2, ylim1, ylim2, sparse, symbol):
 """ plot one species for cycle between xlim1 and xlim2. Parameters species : list which species to plot. mod : string or integer Model (cycle) to plot. xlim1, xlim2 : float Mass coordinate range. ylim1, ylim2 : float Mass fraction coordinate range. sparse : integer Sparsity factor for points. symbol : string which symbol you want to use? """

        mass=self.se.get(mod,'mass')
        Xspecies=self.se.get(mod,'yps',species)
        pyl.plot(mass[0:len(mass):sparse],np.log10(Xspecies[0:len(Xspecies):sparse]),symbol)
        pyl.xlim(xlim1,xlim2)
        pyl.ylim(ylim1,ylim2)
        pyl.legend()