python中几种括号的使用()、[]、{}举例说明

a = ("test1","test2","test3")
b = (1,2,3)
c = ["test1","test2","test3"]
c.append("test4")
list("ABC")
list(["ABC"])
dic = {'name':'Alex','sex"':'boy'}
dic['age'] = 10
dic.get('name')

//方式一：声明、分配空间、赋值一把抓 a等同于b
int[] a = {1,2,3,4};
//声明、分配空间、赋值一把抓
int [] b = new int[]{1,2,3,4};
//方式二：声明、分配空间
int [] c = new int[4];
//赋值
for (int i=0;i<c.length;i++) c[i] = 10*i;
//方式三：声明
int[] d ;
//分配空间
d = new int[4];
//赋值
for (int i=0;i<d.length;i++) d[i] = 10*i;
//声明
int[] e ;
//分配空间、赋值
e = new int[]{1,2,3,4};
System.out.println(Arrays.toString(a));
System.out.println(Arrays.toString(b));
System.out.println(Arrays.toString(c));
System.out.println(Arrays.toString(d));
System.out.println(Arrays.toString(e));

//list集合
List<String> list = new ArrayList<String>();
list.add("a");
//Map集合
Map<String,String> map = new HashMap<String,String>();
map.put("key","value");

list1 = [19, 20, 21]
list2 = ['19', '20', '21']
print(list1)
print(list2)
list1 = ','.join(str(i) for i in list1)
list2 = ','.join(str(i) for i in list2)
print(list1)
print(list2)