Issue with compareHist function

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When I calculating the chi-square distance between 2 histograms in Python 3.7.4 with OpenCV 4.1.2, I use the following code:

 dis = cv2.compareHist(hist1, hist2, cv2.HISTCMP_CHISQR)

When I debugging this, there will be a warning which says 'Expected Ptr<cv::umat> for argument '%s'. It seems like the problem is on the 'method' arguement. And I also try to set the method arguement to 1, or method = 1, still the same problem. Can you talented people here help me figure this problem out, please. And I will be great thank to you guys, love you! Thank you very much!