ProficiencyUtils constructor Null safety

1. baguette
2. ProficiencyUtils
3. ProficiencyUtils
4. ProficiencyUtils constructor

ProficiencyUtils class

1. Constructors
2. ProficiencyUtils
3. Properties
4. hashCode
5. runtimeType
6. Methods
7. noSuchMethod
8. toString
9. Operators
10. operator ==
11. Static methods
12. getProficiencies
13. getProficiency
14. showProficiency