Display Screen or Portion Thereof with a Set of Graphical User Interfaces

The FIGURE is a front view of a display screen or portion thereof with a set of graphical user interfaces according to the new design.

The outermost rectangular broken lines in the FIGURE illustrate a display screen or portion thereof and form no part of the claimed design. The remaining broken lines represent elements of the set of graphical user interfaces that form no part of the claimed design. Brackets shown in the FIGURE are used to indicate a set, and form no part of the claimed design. The graphical user interfaces of the set are arranged relatively on the drawing sheet for the convenience of illustration, and the placement of each graphical user interface relative to another, or to the drawing sheet, forms no part of the claimed design.