'Luminosity distance in Mpc at redshift ``z``.
This is the distance to use when converting between the
bolometric flux from an object at redshift ``z`` and its
bolometric luminosity.
Parameters
z : array-like
Input redshifts.  Must be 1D or scalar.
Returns
d : `~astropy.units.Quantity`
Luminosity distance in Mpc at each input redshift.
See Also
z_at_value : Find the redshift corresponding to a luminosity distance.
References
Weinberg, 1972, pp 420-424; Weedman, 1986, pp 60-62.'

def luminosity_distance(self, z):

    if isiterable(z):
        z = np.asarray(z)
    return ((1.0 + z) * self.comoving_transverse_distance(z))
