Detect Cycles in 2D Grid LeetCode solution in Python

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class Solution:
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    def containsCycle(self, grid: List[List[str]]) -> bool:
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        def getNeighbours(row, col, char):
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            neighbours = []
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            if row > 0 and grid[row - 1][col] == char and not visited[row - 1][col]:
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                neighbours.append([row - 1, col])
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            if col > 0 and grid[row][col - 1] == char and not visited[row][col - 1]:
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                neighbours.append([row, col - 1])
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            if (
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                row < len(grid) - 1
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                and grid[row + 1][col] == char
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                and not visited[row + 1][col]
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            ):
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                neighbours.append([row + 1, col])
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            if (
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                col < len(grid[0]) - 1
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                and grid[row][col + 1] == char
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                and not visited[row][col + 1]
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            ):
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                neighbours.append([row, col + 1])
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            return neighbours
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        def dfs(row, col, char, cyclePresent):
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            if visited[row][col] or cyclePresent:
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                cyclePresent = True
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                return cyclePresent
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            visited[row][col] = True
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            neighbours = getNeighbours(row, col, char)
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            for r, c in neighbours:
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                cyclePresent = dfs(r, c, char, cyclePresent)
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            return cyclePresent
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        visited = [[False for _ in range(len(grid[0]))] for _ in range(len(grid))]
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        cyclePresent = False
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        for row in range(len(grid)):
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            for col in range(len(grid[0])):
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                if cyclePresent:
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                    return True
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                if visited[row][col]:
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                    continue
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                cyclePresent = dfs(row, col, grid[row][col], cyclePresent)
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        return cyclePresent