There is a bug report about this issue.
Until it is fixed, I suggest that you find these constants in the C++ source code, and define them yourself.
Edit:
I was just curious myself. You find them in the file modules/highgui/include/opencv2/highgui.hpp They are:
CAP_PROP_POS_MSEC =0,
CAP_PROP_POS_FRAMES =1,
CAP_PROP_POS_AVI_RATIO =2,
CAP_PROP_FRAME_WIDTH =3,
CAP_PROP_FRAME_HEIGHT =4,
CAP_PROP_FPS =5,
CAP_PROP_FOURCC =6,
CAP_PROP_FRAME_COUNT =7,
CAP_PROP_FORMAT =8,
CAP_PROP_MODE =9,
CAP_PROP_BRIGHTNESS =10,
CAP_PROP_CONTRAST =11,
CAP_PROP_SATURATION =12,
CAP_PROP_HUE =13,
CAP_PROP_GAIN =14,
CAP_PROP_EXPOSURE =15,
CAP_PROP_CONVERT_RGB =16,
CAP_PROP_WHITE_BALANCE_BLUE_U =17,
CAP_PROP_RECTIFICATION =18,
CAP_PROP_MONOCROME =19,
CAP_PROP_SHARPNESS =20,
CAP_PROP_AUTO_EXPOSURE =21, // DC1394: exposure control done by camera, user can adjust refernce level using this feature
CAP_PROP_GAMMA =22,
CAP_PROP_TEMPERATURE =23,
CAP_PROP_TRIGGER =24,
CAP_PROP_TRIGGER_DELAY =25,
CAP_PROP_WHITE_BALANCE_RED_V =26,
CAP_PROP_ZOOM =27,
CAP_PROP_FOCUS =28,
CAP_PROP_GUID =29,
CAP_PROP_ISO_SPEED =30,
CAP_PROP_BACKLIGHT =32,
CAP_PROP_PAN =33,
CAP_PROP_TILT =34,
CAP_PROP_ROLL =35,
CAP_PROP_IRIS =36,
CAP_PROP_SETTINGS =37
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