| Nested Element Summary | 
|   | ContractsA list of contracts that contain most of the
							constraints regarding the assignment of shifts to employees.
 | 
|   | EmployeeListA list of available employees, either as individuals or homogeneous groups of variable size.
 | 
|   | EmployeePairingsThis can be used to model constraints such as
							two or more employees having to work certain shifts at the same time
							or oppositely,
							two or more employees must not work certain shifts
							at the same time.
 | 
|   | SkillsA list of skills (qualifications) relevant for
							the schedule, employees may possess an arbitrary number of
							skills.
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