Python calls a DLL to operate a meter reader

# -*- coding: GBK -*-
from ctypes import *

dll = ('')
a = ()
print 'Test device connection status %s' % a

srcName = c_char_p("publish_pd.bin")
decName = c_char_p('d:\\publish_pd.bin')
b = (srcName,decName)
print 'Uploading file to computer %s' % b

pStr = c_char_p()
= ''
c = (pStr);
print 'Read meter reader time %s' % c
print pSt