如何将字符串插入较大字符串的特定部分？

# 使用插入函数
def insert_string(original_string, insert_string, position):
    return original_string[:position] + insert_string + original_string[position:]

# 使用替换函数
def replace_string(original_string, replace_string, start, end):
    return original_string[:start] + replace_string + original_string[end:]

# 示例用法
original_string = "This is a larger string."
insert_string = "inserted "
position = 8
new_string = insert_string(original_string, insert_string, position)
print(new_string)

replace_string = "replacement"
start = 5
end = 7
new_string = replace_string(original_string, replace_string, start, end)
print(new_string)