Explanation
The condition new() ensures the empty/default constructor and must be the last condition.
When you define a generic class, you can apply restrictions to the kinds of types that client code can use for type arguments when it instantiates your class. If client code tries to instantiate your class by using a type that is not allowed by a constraint, the result is a compile-time error. These restrictions are called constraints.
Constraints are specified by using the where contextual keyword.
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