Display Screen or a Portion Thereof with a Graphical User Interface

FIG. 1 is a front view of a display screen or a portion thereof with a graphical user interface of one embodiment of our new design.

FIG. 2 is a front view of a second image thereof.

FIG. 3 is a front view of a third image thereof.

FIG. 4 is a front view of a display screen or a portion thereof with a graphical user interface of another embodiment of our new design.

FIG. 5 is a front view of a second image thereof; and,

FIG. 6 is a front view of a third image thereof.

The dashed broken line perimeter in the drawings illustrate a display screen or a portion thereof and forms no part of the claimed design. The remaining dashed broken lines in the drawings illustrate portions of the graphical user interface that form no part of the claimed design.

The appearance of the transitional images sequentially transition between the images shown in FIGS. 1 to 3 and FIGS. 4 to 6 , wherein the process or period in which one image transitions to another image forms no part of the claimed design.