it’s also a very good idea to NEVER use magic numbers. use the named constants that exist.
cv2.DrawMatchesFlags_DRAW_OVER_OUTIMG
these identifiers aren’t easy to find but it’s possible:
>>> [x for x in dir(cv2) if 'DrawMatchesFlags' in x]
['DrawMatchesFlags_DEFAULT', 'DrawMatchesFlags_DRAW_OVER_OUTIMG', 'DrawMatchesFlags_DRAW_RICH_KEYPOINTS', 'DrawMatchesFlags_NOT_DRAW_SINGLE_POINTS']