import sys
psApp = None
try:
    if sys.platform == 'darwin':
        from appscript import *
        psApp = app('Adobe Photoshop CS5')
    else:
        from win32com.client import Dispatch
        psApp = Dispatch('Photoshop.Application')
        #import comtypes
        #psApp = comtypes.client.CreateObject('Photoshop.Application')
except:
    pass