[BUG]: Is singlestar.metallicity the absolute mass fraction of metals, or the ratio to solar fraction?

[ezapartas]

In the singlestar class, from what I understand metallicity gets the values from the population run:
setattr(self, 'metallicity', kwargs.pop('metallicity', 1.0))
and
Z_div_Zsun = self.metallicity

However, the declaration of the variable in the singlestar properties is
'metallicity', # initial mass fraction of metals
So I am not sure if for Zsolar, singlestar.metallicity = 0.142 or 1.0
Do we just need to change the comment above next to the declaration?
Can we make sure that we are consistent across the posydon code for the use of singlestar.metallicity?

[sgossage]

@ezapartas thanks, I believe that just the comment needs to change -- it is mass fraction divided by solar mass fraction (e.g., 1.0, not 0.0142). I agree we should double check and make this consistent across the code.