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<filter_flags> could be: ?-unrendered? ?-higherentity <num_higher>? ?-material <id_material>? ?-layer <layer_name>? ?-plane {a b c d r}? ?-avoid_frozen_layers?
-unrendered flag is only valid for surface
-higherentity <num_higher> to filter the selection and list only the entities with the amount of parents equal to <num_higher> (integer >=0)
-material <id_material>to filter the selection and list only the entities with material id equal to <id_material> (integer >=0)
-plane <a b c d r> to list only the entities wigth with center that match the plane equation a*x+b*y+c*z+d<=r
-entity_type <types_allowed> to list only the entities of a type contained in <types_allowed>, that must be a list of allowed types ("STLINE | ARCLINE |POLYLINE | NURBLINE | NURBSURFACE PLSURFACE COONSURFACE MESHSURFACE CONTACTSURFACE VOLUME CONTACTVOLUME")
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