how to use h5 file in python

1import time
2import numpy as np
3import h5py
4import os
5
6arr = np.random.randn(1000)
7
8with h5py.File('groups.hdf5', 'w') as f:
9    g = f.create_group('Base_Group')
10    d = g.create_dataset('default', data=arr)
11
12    g.attrs['Date'] = time.time()
13    g.attrs['User'] = 'Me'
14
15    d.attrs['OS'] = os.name
16
17    for k in g.attrs.keys():
18        print('{} => {}'.format(k, g.attrs[k]))
19
20    for j in d.attrs.keys():
21      print('{} => {}'.format(j, d.attrs[j]))