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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 catvl(z, ver, vnew, lamb, lambnew, br):
 """ trapz integrates over altitude axis, axis = -2 concatenate over reaction dimension, axis = -1 br: column integrated brightness lamb: wavelength [nm] """

    if ver is not None:
        br = np.concatenate((br, np.trapz(vnew, z, axis=-2)), axis=-1)  # must come first!
        ver = np.concatenate((ver, vnew), axis=-1)
        lamb = np.concatenate((lamb, lambnew))
    else:
        ver = vnew.copy(order='F')
        lamb = lambnew.copy()
        br = np.trapz(ver, z, axis=-2)

    return ver, lamb, br