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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 _redshift(distance, **kwargs):
 r"""Uses astropy to get redshift from the given luminosity distance. Parameters distance : float The luminosity distance, in Mpc. \**kwargs : All other keyword args are passed to :py:func:`get_cosmology` to select a cosmology. If none provided, will use :py:attr:`DEFAULT_COSMOLOGY`. Returns ------- float : The redshift corresponding to the given luminosity distance. """

    cosmology = get_cosmology(**kwargs)
    return z_at_value(cosmology.luminosity_distance, distance, units.Mpc)