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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 make_cdisk_kernel(psf, sigma, npix, cdelt, xpix, ypix, psf_scale_fn=None, normalize=False):
 """Make a kernel for a PSF-convolved 2D disk. Parameters psf : `~fermipy.irfs.PSFModel` sigma : float 68% containment radius in degrees. """


    sigma /= 0.8246211251235321

    dtheta = psf.dtheta
    egy = psf.energies

    x = make_pixel_distance(npix, xpix, ypix)
    x *= cdelt

    k = np.zeros((len(egy), npix, npix))
    for i in range(len(egy)):
        def fn(t): return psf.eval(i, t, scale_fn=psf_scale_fn)
        psfc = convolve2d_disk(fn, dtheta, sigma)
        k[i] = np.interp(np.ravel(x), dtheta, psfc).reshape(x.shape)

    if normalize:
        k /= (np.sum(k, axis=0)[np.newaxis, ...] * np.radians(cdelt) ** 2)

    return k