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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 get_gap(self, tol=0.001, abs_tol=False, spin=None):
 """ Expects a DOS object and finds the gap. Args: tol: tolerance in occupations for determining the gap abs_tol: An absolute tolerance (True) and a relative one (False) spin: Possible values are None - finds the gap in the summed densities, Up - finds the gap in the up spin channel, Down - finds the gap in the down spin channel. Returns: gap in eV """

        (cbm, vbm) = self.get_cbm_vbm(tol, abs_tol, spin)
        return max(cbm - vbm, 0.0)