Maximal Square LeetCode solution in Python

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class Solution:
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    def maximalSquare(self, matrix: List[List[str]]) -> int:
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        m, n = len(matrix), len(matrix[0])
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        result = 0
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        dp = [
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            [0] * n for _ in range(m)
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        ]  # dp[x][y] is the length of the maximal square at (x, y)
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        for i in range(m):
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            for j in range(n):
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                if matrix[i][j] == "1":  # ensure this condition first
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                    # perform computation, mind border restrictions
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                    dp[i][j] = (
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                        min(
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                            dp[i - 1][j] if i > 0 else 0,
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                            dp[i][j - 1] if j > 0 else 0,
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                            dp[i - 1][j - 1] if i > 0 and j > 0 else 0,
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                        )
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                        + 1
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                    )
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                    if dp[i][j] > result:
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                        result = dp[i][j]
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        return result * result