Python中的字符串切割和拼接方法的性能比较和最佳实践是什么？

import time

def split_test():
    s = "This is a test string"
    for i in range(10000):
        s.split()

def slice_test():
    s = "This is a test string"
    for i in range(10000):
        s[:].split()

start_time = time.time()
split_test()
end_time = time.time()
print("split()方法耗时：", end_time - start_time)

start_time = time.time()
slice_test()
end_time = time.time()
print("切片操作耗时：", end_time - start_time)

import time

def plus_operator_test():
    s = ""
    for i in range(10000):
        s += str(i)

def join_test():
    s = ""
    strings = [str(i) for i in range(10000)]
    s.join(strings)

start_time = time.time()
plus_operator_test()
end_time = time.time()
print("+号运算符耗时：", end_time - start_time)

start_time = time.time()
join_test()
end_time = time.time()
print("join()函数耗时：", end_time - start_time)