1def is_exchange_rate_valid(exchange_rates):
 2    for currency in exchange_rates:
 3        if len(currency) != 3:
 4            return False
 5        if exchange_rates[currency] <= 0:
 6            return False
 7    return True
 8
 9def курс_в_лева(exchange_rates):
10    if not is_exchange_rate_valid(exchange_rates):
11        return None
12    
13    result = {}
14    for currency in exchange_rates:
15        result[currency] = round(1 / exchange_rates[currency], 4)
16    return result 
17
18def валута_към_левчета(*currencies, **exchange_rates):
19    
20    if not is_exchange_rate_valid(exchange_rates):
21        return None
22
23    sum = {}
24    for currency, amount in currencies:
25        if currency not in sum:
26            sum[currency] = 0
27        sum[currency] += amount
28    
29    result = []
30    for currency in sum:
31        if currency == "BGN":
32            result.append((currency, sum[currency]))
33        else:
34            result.append((currency, round(sum[currency] / exchange_rates[currency], 4)))
35    return result
36
37def е_патриотична(currencies, exchange_rates): 
38
39    if not is_exchange_rate_valid(exchange_rates):
40        return None
41
42    total_sum = 0
43
44    for currency, amount in currencies:
45        if currency == "BGN":
46            total_sum += amount
47        else: 
48            total_sum += (amount / exchange_rates[currency])
49    
50    rounded = round(total_sum, 2)
51    if rounded % 1 == 0:
52        return "ПАТРИОТИЧНА!"
53    else: 
54        return "НЕПАТРИОТИЧНА!"
55