>>> test1 = {"zhangsan":["java","c","python"],"lisi":["c++","golang"],"wangwu":["c","java","python","javascript"]}
>>> type(test1)
<class 'dict'>
>>> len(test1)
3
>>> for i,j in test1.items():
print("\n",i)
for k in j:
print(k)
zhangsan
java
c
python
lisi
c++
golang
wangwu
c
java
python
javascript
>>> test1["zhaoliu"]=["python"]
>>> test1
{'zhangsan': ['java', 'c', 'python'], 'lisi': ['c++', 'golang'], 'wangwu': ['c', 'java', 'python', 'javascript'], 'zhaoliu': ['python']}
>>> len(test1)
4
>>> for i,j in test1.items():
if len(j) == 1:
print(f"\n{i}'s favorite language is {j[0]}")
else:
print("\n",i)
for k in j:
print(k)
zhangsan
java
c
python
lisi
c++
golang
wangwu
c
java
python
javascript
zhaoliu's favorite language is python