LeetCode ASMR: Lemonade Change | Day 60 Coding Chill

This is making me want to set up a lemonade stand : D

[@LeekCodeDev]

Source Code:
class Solution:
def lemonadeChange(self, bills: List[int]) -> bool:
"""
To solve this problem, I first tried to write down all the
possible scenarios. Because I need to give my customers
a net change of 5 dollars, 3 things can happen:
Customer gives me $5 -> I just add my number of 5 dollar bills
Customer gives me $10 -> I give them one of my 5 dollar bills
if I have any. If not, I return False
Customer gives me $20 -> I give them 1 10$ bill and 1 5$ bill,
or give them 3 5$ bills, given that I have enough bills. If I
don't, I return False.
I'm going to keep my counts of 5 dollar bills and 10 dollar
bills in a hash map. :D
"""
bank = defaultdict(int)
for bill in bills:
if bill == 5:
bank[bill] += 1
elif bill == 10:
if bank[5] < 1:
return False
else:
bank[5] -= 1
bank[10] += 1
else:
if bank[5] > 0 and bank[10] > 0:
bank[5] -= 1
bank[10] -= 1
elif bank[5] >= 3:
bank[5] -= 3
else:
return False
return True