Represents the section object.
The section object is created from a part document in which a sketch has to
be defined.
The sketch object may contain one or several contour but all of them have
to be closed.
Predefined anchor points objects are calculated from the geometrical contour
as the top bottom point, the center gravity point, etc.
User anchor points can be created in the sketch using the parametric geometry
or not. However the names of these points have to prefixed by the string "Str"
to be recognized as structure anchor points.
Some attributes are defined on the section object but cannot be modified.
A group of attributes defines the section name, the family name, and the
the name of the catalog where the section comes from.
Another attribute called the profile type defines the type of the parametric
contour used to create the section. The contour can be a Tee, an angle, a channel,
a square tube, and so on. These predefined contours are useful to create a new
catalog with some standard contours.