How to create a new function in the SikuliRemoteLibrary.py under the framework of RF+selenium+sikuli

Eenvironment: Robot Framework 2.8.4
                              Python 2.7.5 on win32
                              RIDE 1.2.3
                              java version "1.6.0_45"
                              sikuli r930

Description：I use robotremoteserver.py SikuliRemoteLibrary.py sikuli-script.jar connect RF+selenium sikuli together. But I found that SikuliRemoteLibrary.py comes with the function is not enough. so I need to define a new function. So here comes the question...

Question:

check_object_exists_right() is a new function I define ,but it doesn't work well.
class SikuliRemoteLibrary:

    def __init__(self):
        self.SS = Screen()
        self.PT = Pattern()

    def check_object_exists_right(self, imgFile, position, space, Find_imgFile, timeOut, similarity):
        try:
            find = self.SS.click(self.SS.find(imgFile).left(500).find(Find_imgFile))
            print find
        finally:
                state = 1
        return state

the testcase in RIDE is:
check object exists right ${图片路径}\\Camera_Setup.png left 500 ${图片路径}\\set-menu-icon-off.png 10 0.91

RIDE execute error log:
20160413 20:42:25.161 : FAIL : ImportError: No module named sikuli
20160413 20:42:25.162 : DEBUG :
Traceback (most recent call last):
  File "SikuliRemoteLibrary.py", line 13, in check_object_exists_right
    find = self.SS.click(self.SS.find(imgFile).left(500).find(Find_imgFile))
  File "<string>", line 1, in <module>

WHY:
          I find that,when it define like this it will works well.
          find = self.SS.click(self.SS.find(imgFile))

          but if it define like this it will be error .
          find = self.SS.click(self.SS.find(imgFile).left(500).find(Find_imgFile))

          And if I define like this only run by sikulir930 or run by Eclipse+Selenium2+sikuli-script.jar ,it works well too.
          find = self.SS.click(self.SS.find(imgFile).left(500).find(Find_imgFile))

so,how can I define a new function to use this codes: find = self.SS.click(self.SS.find(imgFile).left(500).find(Find_imgFile))

thanks a lot !