如何在2d数组中找到最常见的int？

def find_most_common_int(arr):
    count_dict = {}
    for row in arr:
        for num in row:
            if num in count_dict:
                count_dict[num] += 1
            else:
                count_dict[num] = 1

    most_common_int = max(count_dict, key=count_dict.get)
    return most_common_int

# 示例
arr = [
    [1, 2, 3],
    [2, 3, 4],
    [3, 4, 5],
    [1, 2, 3]
]

result = find_most_common_int(arr)
print(result)  # 输出：1