'name':'Alice'},{'id':2,'name':'Bob'},]@app.route('/users')defget_users():return jsonify(users=users)这里 ，Flask框架的jsonify函数将列表转换为JSON格式并设置正确的响应头，客户端接收到的响应类似于：{"users":[{"id":1,"name":"Alice"},{"id"
我们可以用方括号[],指定key访问到对应的value。 dev_ip = dev_info['ip'] print(dev_ip) # 输出结果是'192.168.1.1' 如果字典中无此key,则程序会报错,另有一种安全的访问方法,是字典的get方法,它的逻辑是: 如果有对应的键值对,返回其值, 如果无则返回一个默认值,如果我们没指定默认值,则返回特殊的...
importcollections Sale=collections.namedtuple('Sale','productid customerid data quantity price')sales=list()sales.append(Sale(432,921,"2018-04-01",3,8.2))sales.append(Sale(543,879,"2018-03-31",6,8.1))print(sales)[out][Sale(productid=432,customerid=921,data='2018-04-01',quantity=3,pr...
position (0th index), looking for the element you are searching for. When it finds the value - it returns the position and exits the system. However, this is not too efficient when going through a large list, and you need to get the position of something towards the end of the list....
1list1=["Java","Python","Go"]2print(list1.index("Go")) 运行结果如下: 获取对象的个数:count() 1list1=["Java","Python","Go"]2print(list.count("Go")) 运行结果如下: 复制对象:copy() 1list1=["Java","Python","Go"]2list2=list1.copy()3print(list2) ...
老Python带你从浅入深探究List 列表 Python中的列表(list)是最常用的数据类型之一。 Python中的列表可以存储任意类型的数据,这与其他语言中的数组(array)不同。 被存入列表中的内容可称之为元素(element)或者数据项(data item)亦或是值(value)。 虽然Python列表支持存储任意类型的数据项,但不建议这么做,事实上...
❮ List Methods ExampleGet your own Python Server What is the position of the value "cherry": fruits = ['apple','banana','cherry'] x = fruits.index("cherry") Try it Yourself » Definition and Usage Theindex()method returns the position at the first occurrence of the specified value...
We can get the index of the first element in our list using the index() function.first_index = my_list.index('a') print(first_index) # 0As you can see, my_list.index('a') returns the index of the first element ‘a’ in my_list, which is 0....
代码语言:javascript 代码运行次数:0 运行 AI代码解释 importtkinterimporttime defgettime():var.set(time.strftime("%H:%M:%S"))# 获取当前时间 root.after(1000,gettime)# 每隔1s调用函数 gettime 自身获取时间 root=tkinter.Tk()root.title('时钟')var=...
acclist.index() 调出list中内容位置 acclist.insert() (要插入的位置,插入的内容) list插入内容 acclist.remove(value) 指要删除的list中的内容(找到的第一个value) acclist.count(‘value’) 查找list中有多少个value acclist[4] = ‘value’ 更改某个位置的元素 ...