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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 diff_flux_threshold(self, skydir, fn, ts_thresh, min_counts):
 """Compute the differential flux threshold for a point source at position ``skydir`` with spectral parameterization ``fn``. Parameters skydir : `~astropy.coordinates.SkyCoord` Sky coordinates at which the sensitivity will be evaluated. fn : `~fermipy.spectrum.SpectralFunction` ts_thresh : float Threshold on the detection test statistic (TS). min_counts : float Threshold on the minimum number of counts. """


        sig, bkg, bkg_fit = self.compute_counts(skydir, fn)
        norms = irfs.compute_norm(sig, bkg, ts_thresh,
                                  min_counts, sum_axes=[2, 3],
                                  rebin_axes=[10, 1],
                                  bkg_fit=bkg_fit)

        npred = np.squeeze(np.apply_over_axes(np.sum, norms * sig, [2, 3]))
        norms = np.squeeze(norms)

        flux = norms * fn.flux(self.ebins[:-1], self.ebins[1:])
        eflux = norms * fn.eflux(self.ebins[:-1], self.ebins[1:])
        dnde = norms * fn.dnde(self.ectr)
        e2dnde = self.ectr**2 * dnde

        return dict(e_min=self.ebins[:-1], e_max=self.ebins[1:],
                    e_ref=self.ectr,
                    npred=npred, flux=flux, eflux=eflux,
                    dnde=dnde, e2dnde=e2dnde)