The ornamental design for a displayscreen with a graphical user interface, as shown and described.
FIG. 1 is a front view of a first image in a sequence for a display screen with a graphical user interface showing the claimed design.
FIG. 2 is a front view of a second image thereof; and,
FIG. 3 is a front view of a third image thereof.
The outermost broken lines illustrate a mobile device, which is the environment of the design, and form no part of the claimed design. The remaining broken lines illustrate the display screen and portions of the graphical user interface and form no part of the claimed design.
The appearance of the image sequentially transitions between the images shown in FIGS. 1 through 3. The process or period in which one image transitions to another forms no part of the claimed design.