def METHOD_NAME(cosmo, k, a):
    """The linear matter power spectrum
    Args:
        cosmo (:class:`~pyccl.cosmology.Cosmology`): Cosmological parameters.
        k (:obj:`float` or `array`): Wavenumber; :math:`{\\rm Mpc}^{-1}`.
        a (:obj:`float` or `array`): Scale factor.
    Returns:
        (:obj:`float` or `array`): Linear matter power spectrum;
        :math:`{\\rm Mpc}^3`.
    """
    return cosmo.linear_power(k, a, p_of_k_a=DEFAULT_POWER_SPECTRUM)