How to specify manditory arguments

Derived from discussion about parent issue #216 (closed) within LC-Types:

It should be discussed how it is possible to specify manidtory fields in an intuitive way.

The following proposal was taken from the parent issue #216 (closed), which allows taht in a python way:

# Some fields are mandatory and some are default 
struct OdrExplicitPoint 
    odr_id: int      # Mandatory to be set by user
    lane_id: int     # Mandatory to be set by user
    # If not set, choose as default something in this range (Default range is not equal to constraints!)
    offset: distance = randomize(-1..1)
    
    # Additionally we add constraints - We want this never to happen
    keep(offset < 10)
    keep(offset > -10)

# This allows now to call it the following way:

# distance will be randomized  within default value bounds
point_1: OdrExplicitPoint(odr_id = 1, lane_id = 2)

# distance is set (outside of default range)
point_2: OdrExplicitPoint(odr_id = 1, lane_id = 2, offset = randomize(-2..2)

# ERROR: This is not possible, as it is a contradiction to the constraints
point_3: OdrExplicitPoint(odr_id = 1, lane_id = 2, offset = 2000)