items() Returns an object in the dictionary’s list of items in the form of key-value pair. dictionary_name.items() clear() Removes all the dictionary items. dictionary_name.clear() copy() Returns a shallow copy of the dictionary. dictionary2 = dictionary1.copy() update(dict) Updates th...
The len() function in Python helps in getting the length of any type of data, like a string, list, or tuple. The len() function is used to get the length (number of elements) of an object like a string, list, dictionary, or set. Example 1: Python 1 2 3 4 # Using len() ...
列表定义 定义:列表就是用中括号包围、逗号隔开的任何东西(称作元素element),没有数量,长度限制。用中括号[]加序号访问列表元素的方法就是索引index,索引就是列表元素所在的位置,索引从0 而不是1 开始,第二个元素索引为1,第三个索引为2,依次类推。 列表元素访问 修改,添加 各种删除方法 列表切片读取内容 切片的...
'Chico', 'Harpo') >>> marx_dict = {'Groucho': 'banjo', 'Chico': 'piano', 'Harpo': 'harp'} >>> marx_set = {'Groucho', 'Chico', 'Harpo'} >>> marx_list[2] 'Harpo' >>> marx_tuple[2] 'Harpo' >>> marx_dict['Harpo'] 'harp' >>> 'Harpo' in marx_list True >>> ...
As you can probably see here, we are using the index of0and the index of4, but our list actually only has3indexes (0, 1, 2, 3, 4). We need to use4as the end index becauselist slicing does not include the last index by default, meaning if we would try to useprint(our_list[...
A step value of -1 reverses the list:>>> fruits[::-1] ['orange', 'lemon', 'pear', 'kiwi', 'lime', 'apple', 'watermelon'] Whenever a negative step value is given, the default meaning of start and stop change. With a negative step value, the start value will default to the ...
A slice is typed between square brackets, like an index, but it has two integers separated by a colon. Notice the difference between indexes and slices. spam[2] is a list with an index (one integer). spam[1:4] is a list with a slice (two integers). In a slice, the first ...
To write a Python function, you need a header that starts with the def keyword, followed by the name of the function, an optional list of comma-separated arguments inside a required pair of parentheses, and a final colon. The second component of a function is its code block, or body. ...
Dictionary is created using curly braces with key and value separated by semicolon{Key : Value}. Similar to list, dictionaries objects are mutable data type meaning objects can be modified once the dictionary is created. The construct of dictionary implementation in python is more generally known ...
Thesort()method sorts the elements of a list in place, meaning it modifies the original list. It does not return a new list. fruits=['apple','banana','orange','grape']fruits.sort()print(fruits) 1. 2. 3. Output: ['apple', 'banana', 'grape', 'orange'] ...