The ornamental design for a christmastreelight, as shown and described.
FIG. 1 is a perspective view of a Christmas tree light showing my new design;
FIG. 2 is a front view thereof;
FIG. 3 is a back view thereof;
FIG. 4 is a left side view thereof;
FIG. 5 is a right side view thereof;
FIG. 6 is a top view thereof;
FIG. 7 is a bottom view thereof;
FIG. 8 is an exploded view of the Christmas tree light thereof;
FIG. 9 is an enlarged view of the selected portion in FIG. 1; and,
FIG. 10 is an enlarged view of the selected portion in FIG. 1.
The broken lines shown in the drawings depict portions of the Christmas tree light in which the design is embodied that form no part of the claimed design. The dash-dot-dash broken encircling the enlarged views in FIGS. 1, 3, 9 and 10 are for annotative purposes only and form no part of the claim thereof. The Christmas tree light is shown with symbolic breaks in its length. The appearance of any portion of the article between the break lines forms no part of the claimed design.