Calculate Price

py

import json

def calculate(filename):
    with open(filename) as f:
        data = json.load(f)
    for i in data:
        data[i] = data[i]/300 * 0.6 # <- that is the percentage of actual price you want to sell for.
    return data

print(calculate('prices.json')) # <- this is the name of the file you want to use.