Python Detect Keystrokes Sent to Another Application

I have a Python program that sends keystrokes to another application using SendKeys. Some of the keystrokes, however, must be sent to the application after it does some processing (which takes an unknown amount of time). So far I have had to let the Python application know th开发者_如何学Ce processing was finished by Alt+Tabbing back to the DOS window and hitting Enter. I'd like to have a key combination (Shift+F1 or something like that) that I can hit in the receiving application that signals the Python program to continue without me having to switch back to the DOS window. How would I make it so I can detect keystrokes in Python even though the focus is on another window?

Have a look at pyHook.

It allows Keyboard hooking:

import pythoncom, pyHook 

def OnKeyboardEvent(event):
  print 'MessageName:',event.MessageName
  print 'Message:',event.Message
  print 'Time:',event.Time
  print 'Window:',event.Window
  print 'WindowName:',event.WindowName
  print 'Ascii:', event.Ascii, chr(event.Ascii)
  print 'Key:', event.Key
  print 'KeyID:', event.KeyID
  print 'ScanCode:', event.ScanCode
  print 'Extended:', event.Extended
  print 'Injected:', event.Injected
  print 'Alt', event.Alt
  print 'Transition', event.Transition
  print '---'

# return True to pass the event to other handlers
  return True

# create a hook manager
hm = pyHook.HookManager()
# watch for all mouse events
hm.KeyDown = OnKeyboardEvent
# set the hook
hm.HookKeyboard()
# wait forever
pythoncom.PumpMessages()