Someone can explain me this code?

Question

data = {
"100-90": 25, "42-01": 48, "55-09": 12, "128-64": 71, "002-22": 18, "321-54": 19, "097-32": 33, "065-135": 64, "99-043": 80, "111-99": 11, "123-019": 5, "109-890": 72, "132-123": 27, "32-908": 27, "008-09": 25, "055-967": 35, "897-99": 44, "890-98": 56, "344-32": 65, "43-955": 59, "001-233": 9, "089-111": 15, "090-090": 17, "56-777": 23, "44-909": 27, "13-111": 21, "87-432": 15, "87-433": 14, "87-434": 23, "87-435": 11, "87-436": 12, "87-437": 16, "94-121": 15, "94-122": 35, "80-089": 10, "87-456": 8, "87-430": 40
}
age = int(input())
orgsum = 0
suma = 0

for i in data.values():
if i >= 18:
orgsum += 20
else:
orgsum += 5

for i in data.values():
if i < age:
suma += 5
else:
suma += 20

total = int(100*((orgsum - suma)/orgsum))
print(abs(total))

Answer 1

The first loop adds 20 points for each value that is >= 18 and 5 points otherwise.

The second loop adds 5 points for each value < age (input) and 20 otherwise.

The second last line calculates the difference of the two sums and gives the proportion difference/orgsum

Answer 2

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