CLAIM The ornamental design for a user interface for a portion of a display screen, as shown and described.
Description:
The FIGURE is a front view of a user interface for a portion of a display screen showing our new design.
The broken line drawing of the square and the area within the square screen is for illustrative purposes only and forms no part of the claimed design. The broken line showing of the display screen is for illustrative purposes only and forms no part of the claimed design.