python 讀取二進制文件 轉為16進制輸出

示例：

#!/usr/bin/env python
#encoding: utf-8
import binascii
fh = open(r'C:\Temp\img\2012517165556.png', 'rb')
a = fh.read()
#print 'raw: ',`a`,type(a)
hexstr = binascii.b2a_hex(a)
print a
print hexstr #示意結果為4d5a900003000000....