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##
##  congsemigraph.gd
##  Copyright (C) 2022                     Marina Anagnostopoulou-Merkouri
##                                                          James Mitchell
##
##  Licensing information can be found in the README file of this package.
##
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DeclareCategory("IsCongruenceByWangPair",
                IsSemigroupCongruence
                and CanComputeEquivalenceRelationPartition
                and IsMagmaCongruence
                and IsAttributeStoringRep
                and IsFinite);

DeclareOperation("CongruenceByWangPair",
                 [IsGraphInverseSemigroup,
                  IsHomogeneousList,
                  IsHomogeneousList]);

DeclareOperation("AsCongruenceByWangPair", [IsSemigroupCongruence]);

DeclareOperation("MinimalHereditarySubsetsVertex",
                 [IsGraphInverseSemigroup, IsPosInt]);

DeclareAttribute("GeneratingCongruencesOfLattice", IsGraphInverseSemigroup);