Movie Theater Problem

movie_theater.py

input = ['2020-01-01,Soda',
        '2020-01-03,Soda',
        '2020-01-02,Popcorn',
        '2020-01-05,Soda',
        '2020-01-06,Popcorn',
        '2020-01-07,Soda',
        '2020-01-02,Popcorn',
        '2020-01-12,Soda',
        '2020-01-03,Popcorn',
        '2020-01-22,Soda',
        '2020-01-05,Soda',
        '2020-01-18,Popcorn',
        '2020-01-13,Soda',
]

pricing = {
    "Soda":20,
    "Popcorn":10,
    "Combo": 25
}

class DayBill:
    items = []

    def __init__(self,item):
        self.items.append(item)

    def calcPrice(self):
        combo = 0
        soda = 0
        popcorn = 0

        for item in self.items:
            if item == "Soda":
                soda = soda + 1
            if item == "Popcorn":
                popcorn = popcorn + 1

        while(soda > 1 and popcorn >1):
            combo = combo + 1
            soda = soda - 1
            popcorn = popcorn - 1
        
        return (combo * pricing['Combo']) + (soda * pricing['Soda']) + (soda * pricing['Popcorn'])
        
        

items_by_date_dict = {}
for item in input:
    date,item = item.split(',')

    if date in items_by_date_dict:
        items_by_date_dict[date].items.append(item)
    else:
        items_by_date_dict[date] = DayBill(item)

bill = 0
for date in items_by_date_dict:
    bill = bill + items_by_date_dict[date].calcPrice()

print(bill)