python3 os.urandom

# os.urandom(n)
# Return a string of n random bytes suitable for cryptographic use.
# This function returns random bytes from an OS-specific randomness source.

import os
import hashlib

for i in range(1, 11):
    bytes_20 = os.urandom(20)
    print("%s: %s" % (i, bytes_20))
    hex_32 = hashlib.md5(bytes_20).hexdigest()
    print("%s: %s" % (i, hex_32))

执行结果：

1: b'x84{<8x84x17xbb^uxa9xa0xd2xcfx8ex0czxa8xbe~xcd'
1: e0cb861e7851a1a7f766e89e235aa2ca
2: b'`xfe!yxf3xedxbex06tx18x80xe8xadxadax95xb0fxd4C'
2: cce8bef3a22aecc082c91054ec7c6bf5
3: b'xd2x1cx96x90xd1dWxa0xfbYxdd/;xee2x06xbaRx1es'
3: a7902517133c44535c8686fba28770e4
4: b'?Yxbbx00rOxf0xa1x82#xff+{bx85x8eDN xb1'
4: cdc8468ffa5642afeb1b94bb6bed6bd7
5: b'&U_8hxfaDxf8xf5)xb3YPxe6xedxdb
#G}'
5: f61fe7fdaaa9dac6c15022997db804eb
6: b'xc0xabxaaFxcaxe7yx93zx10xx7fYxe7jWQ}xae3'
6: 3cbdd329f5a4ce371b777ed55cdf889a
7: b'x18xffx8cx96x89xd6x01xxdax12xb5xc4xd2Y/ixf8Nx85xb0'
7: d24b45ca762be51d07f9b8cb236239d3
8: b'xbex10RHxd8x9d*dxd2xdaxd9Wx1bCxa4xcdx9fqx167'
8: 417bc71a045858fca7bb754dc238d5eb
9: b'Fvxe9x07
x95xe4xc9Wxdbxbb=xe3m5xd8x8dxca@x16'
9: 44f83197dd35d1678cf4e356ca03e3ba
10: b'[xca4Qtxd46xdfxc4xbd>xe2x9dx89xa0<x9c{?xe2'
10: a8826d75b0054f3c9021b648e477a30e