1d = {1:2, 3:4}
2print(len(d))
3d.update(["ab"])
4print(d[1])
5print(d[3])
6print(d["a"])
7print(len(d))
8d.update([(1,4)])
9print(d[1])
10print(len(d))
11
12# using keywords
13d.update(a=5)
14print(d['a'])
15d.update([(1,5)], b=6)
16print(d[1], d['b'])
17