A set built from a list with repeats

Predict the outputEasyPython only

main.py

nums = [3, 1, 3, 2, 1]
s = set(nums)
print(len(s))
print(sorted(s))
print(2 in s, 5 in s)
s.add(3)
print(len(s))

What does it print?

Graded by exact match. Spaces at the ends of lines and blank lines at the end do not count.

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