def get_acroversion():
    """ Return version of Adobe Acrobat executable or None"""
    from six.moves import winreg
    adobesoft = winreg.OpenKey(winreg.HKEY_LOCAL_MACHINE, 'Software\\Adobe')
    for index in range(winreg.QueryInfoKey(adobesoft)[0]):
        key = winreg.EnumKey(adobesoft, index)
        if 'acrobat' in key.lower():
            acrokey = winreg.OpenKey(winreg.HKEY_LOCAL_MACHINE, 
                'Software\\Adobe\\%s' % key)
            for index in range(winreg.QueryInfoKey(acrokey)[0]):
                numver = winreg.EnumKey(acrokey, index)
                try:
                    res = winreg.QueryValue(winreg.HKEY_LOCAL_MACHINE, 
                        'Software\\Adobe\\%s\\%s\\InstallPath' % (key, numver))
                    return res
                except Exception:
                    pass
    return None
