def _create_blank(width, height):
    """Returns a 2D list filled with None elements.

    Creates and returns a list of lists of the given dimensions
    filled with None elements.

    Args:
        width: The width of the blank terrain to generate.
        height: The height of the blank terrain to generate.
    """
    # Use a list comprehension to generate a blank of the given dimensions
    empty_terrain = [[None for i in range(width)] for j in range(height)]

    # Return the list
    return empty_terrain