operation is produced they gradually weaken and break exercising the same function as the elastic band s alternatively the sliding cord could be replaced by two cords and in this case the edging will have two exit holes one on each side of the bag the first cord will come out through one of the exit holes and the second cord will come out through the other exit hole with the end of the first cord being supported with a sliding knot to the second cord near the second exit hole and with the end of the second cord being supported with a sliding knot to the first cord near the first exit hole in this case respective gripping means will be arranged on each end of the two cords so that the user will take both gripping elements in their hand and by pulling them upwards will close the bag mouth in both embodiments one single cord with elastic band s or two cords the sliding knot s will be of the flange type in other words that they will allow the cord to slide only in one direction other details and characteristics will become apparent during the description given below with reference to the drawings accompanying this specification which show an illustrative non limiting example of a practical embodiment of the invention fig1 is a top plan view of a first embodiment of the device for picking up dog waste 10 fig2 is a front elevation view of the device for picking up dog waste 10 in fig1 fig3 is a top plan view of a.