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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 _latex_(self):
 r"""The LaTeX routine for states. '^{85}\\mathrm{Rb}\\ 5S_{1/2}' '^{85}\\mathrm{Rb}\\ 5S_{1/2}^{2}' '^{85}\\mathrm{Rb}\\ 5S_{1/2}^{2,2}' """

        if self.l == 0: l = 'S'
        elif self.l == 1: l = 'P'
        elif self.l == 2: l = 'D'
        elif self.l == 3: l = 'F'
        else: l = str(self.l)

        if self.f is None:
            s = '^{'+str(self.isotope)+'}\\mathrm{'+self.element+'}\\ '
            s += str(self.n)+l+'_{'+str(self.j)+'}'
        else:
            s = '^{'+str(self.isotope)+'}\\mathrm{'+self.element+'}\\ '
            s += str(self.n)+l+'_{'+str(self.j)+'}^{'+str(self.f)+'}'

        if self.m is not None:
            s = s[:-1] + ','+str(self.m)+'}'

        return s