N-th Tribonacci Number Python Solution

lcpy gen -n 1137   # by problem number
lcpy gen -s n_th_tribonacci_number   # by problem name

Input: n = 4
Output: 4
Explanation:
T_3 = 0 + 1 + 1 = 2
T_4 = 1 + 1 + 2 = 4

Input: n = 25
Output: 1389537

class Solution:
    # Time: O(n)
    # Space: O(1)
    def tribonacci(self, n: int) -> int:
        if n == 0:
            return 0
        if n == 1 or n == 2:
            return 1

        t0, t1, t2 = 0, 1, 1
        for _ in range(3, n + 1):
            t0, t1, t2 = t1, t2, t0 + t1 + t2
        return t2