Unable to create injector, see the following errors:

1) [Guice/DuplicateMapKey]: Duplicate key "first" found in Map<String, String>.

Duplicates:
  Key: "first"
  Bound at:
    1 : DuplicateMapKeyErrorTest$MapModule.configure(DuplicateMapKeyErrorTest.java:32)
    2 : DuplicateMapKeyErrorTest$MapModule.configure(DuplicateMapKeyErrorTest.java:33)
    3 : DuplicateMapKeyErrorTest$ContributorModule.provideFirstIntoMap(DuplicateMapKeyErrorTest.java:47)

MapBinder declared at:
  DuplicateMapKeyErrorTest$MapModule.configure(DuplicateMapKeyErrorTest.java:31)
      \_ installed by: DuplicateMapKeyErrorTest$MapModule -> RealMapBinder

1 error

======================
Full classname legend:
======================
DuplicateMapKeyErrorTest$ContributorModule: "com.google.inject.errors.DuplicateMapKeyErrorTest$ContributorModule"
DuplicateMapKeyErrorTest$MapModule:         "com.google.inject.errors.DuplicateMapKeyErrorTest$MapModule"
RealMapBinder:                              "com.google.inject.internal.RealMapBinder"
========================
End of classname legend:
========================
