要在Python中合并数组，可以使用以下几种方法：
arr1 = [1, 2, 3]
arr2 = [4, 5, 6]
combined_arr = arr1 + arr2
print(combined_arr)
# 输出：[1, 2, 3, 4, 5, 6]
arr1 = [1, 2, 3]
arr2 = [4, 5, 6]
arr1.extend(arr2)
print(arr1)
# 输出：[1, 2, 3, 4, 5, 6]
arr1 = [1, 2, 3]
arr2 = [4, 5, 6]
arr3 = [7, 8, 9]
arr1.extend(arr2 + arr3)
print(arr1)
# 输出：[1, 2, 3, 4, 5, 6, 7, 8, 9]
arr1 = [1, 2, 3]
arr2 = [4, 5, 6]
arr3 = [7, 8, 9]
combined_arr = [x for arr in [arr1, arr2, arr3] for x in arr]
print(combined_arr)
# 输出：[1, 2, 3, 4, 5, 6, 7, 8, 9]
