vape_juice_calc.py

from typing import List
from dataclasses import dataclass
from numbers import Number


@dataclass
class Liquid:
    volume: int
    mg_per_ml: Number


def wat(*args: List[Liquid]) -> Liquid:
    current_volume = 0
    current_total_mg = 0
    liquids_count = 0
    for l_num, liquid in enumerate(args, start=1):
        print(f"Liquid #{l_num} -> using {liquid.volume}ml @ {liquid.mg_per_ml}mg per ml.")
        adding_mg = liquid.volume * liquid.mg_per_ml
        current_volume += liquid.volume
        current_total_mg += adding_mg
        liquids_count += 1
    print("Total volume:", current_volume)
    print("Total mg:", current_total_mg)
    print("Result:", current_total_mg / current_volume, "mg/ml")

l1 = Liquid(10, 6)
l2 = Liquid(15, 0)

wat(l1, l2)

l3 = Liquid(5, 20)

wat(l1, l2, l3)


>>> wat(l1, l2, l3)
Liquid #1 -> using 10ml @ 9mg per ml.
Liquid #2 -> using 15ml @ 0mg per ml.
Liquid #3 -> using 7ml @ 20mg per ml.
Total volume: 32
Total mg: 230
Result: 7.1875 mg/ml

^ last batch, poured 10ml (remove from each proportionately)