1，复制文件
import shutil
shutil.copyfile('test.txt','test2.txt')
2，把嵌套的列表合并成一个列表
list = [[0, 1, 2], [3, 4, 5]]
result = [item for sublist in list for item in sublist]
print(result)
3，反转列表
numbers = [0, 1, 2, 3, 4, 5, 6, 7, 8]
print(numbers[::-1])
4，列表中最长的字符串
words = ['This', 'is', 'my', 'home', 'and', '...']
result = max(words, key=len)
print(result)
5，列表推导式
list = [num for num in range(0, 10)]
print(list)
6，集合推导式
num_set = {num for num in range(0, 10)}
print(num_set)
7，字典推导式
dict_numbers = {x: x*x for x in range(1, 5)}
print(dict_numbers)
8，使用print语句写入文件
print("Hello, World!", file=open('file.txt', 'w'))
9，计算一个字符在字符串中出现的频率
print("umbrella".count('l'))
10，合并列表
list1 = [1, 2, 4]
list2 = ['XiaoF']
list1.extend(list2)
print(list1)
11，合并字典
dict1 = {'name': 'weiwei', 'age': 23}
dict2 = {'city': 'Beijing'}
dict1.update(dict2)
print(dict1)
12，合并集合
set1 = {0, 1, 2}
set2 = {11, 12, 13}
set1.update(set2)
print(set1)
13，列表中出现次数最多的元素
list = [9, 4, 5, 4, 4, 5, 9, 5, 4]
most_frequent_element = max(set(list), key=list.count)
print(most_frequent_element)
