Be sure to reference the context (e.g. language and device) in question so that others will understand better.
I always use the full Vx in C++ code but I believe the V is optional even there.
And I never see the V in JS… and don’t have a clue in Python 
but based on what you are showing… I see references to what you could consider ‘V1’ and ‘V2’ as those numbers in () would never represent a physical pin in a Blynk command.
PS please format any posted code as per the Welcome Topic, thanks.