restore and deprecate constraints

Author: manueldeprada

src/transformers/__init__.py

@@ -653,6 +653,9 @@
     from .generation import BayesianDetectorModel as BayesianDetectorModel
     from .generation import ClassifierFreeGuidanceLogitsProcessor as ClassifierFreeGuidanceLogitsProcessor
     from .generation import CompileConfig as CompileConfig
+    from .generation import Constraint as Constraint
+    from .generation import ConstraintListState as ConstraintListState
+    from .generation import DisjunctiveConstraint as DisjunctiveConstraint
     from .generation import EncoderNoRepeatNGramLogitsProcessor as EncoderNoRepeatNGramLogitsProcessor
     from .generation import EncoderRepetitionPenaltyLogitsProcessor as EncoderRepetitionPenaltyLogitsProcessor
     from .generation import EosTokenCriteria as EosTokenCriteria