[AstroPy] Aggregate Magnitude of Multiple Star System?

[Jim Singh]

Hi,
When I use astropy to retrieve fluxdata(V) from SIMBAD for 'Acrux', it
returns values for the components alpha1 and alpha2 Crucis as follows:
alf01 Cru: 1.28
alf02 Cru: 1.58
Now, using mathplotlib I am directly translating the fluxdata(V) value to a
'star size' for depicting the relative apparent magnitude of the stars. In
the above case if I 'zoom in' enough such that the angular separation is
sufficient to render two distinct disks, then I can size them according to
the two values. But if I zoom out such that the disks are superimposed on
each other and basically show as one, then I need to somehow translate the
contribution from both components: 1.28 and 1.58, to 0.77 for the  disk to
be the correct size relative to other stars in the plot. Is there an
astropy function that can do this, or alternatively an expression?
I found this expression for example:
https://www.astro.keele.ac.uk/jkt/pubs/JKTeq-fluxsum.pdf
which plugging in m1=1.28 and m2=1.58 yields mTot=0.67, not too far from
the Acrux apparent magnitude of 0.77

Regards,
Jim
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