@Override
        public Builder flattenMixins() {
            if (getMixins().isEmpty()) {
                return this;
            }

            for (Shape mixin : getMixins().values()) {
                for (MemberShape member : mixin.members()) {
                    SourceLocation location = getSourceLocation();
                    Collection<Trait> localTraits = Collections.emptyList();

                    MemberShape existing;
                    if (member.getMemberName().equals("key")) {
                        existing = key;
                    } else {
                        existing = value;
                    }

                    if (existing != null) {
                        localTraits = existing.getIntroducedTraits().values();
                        location = existing.getSourceLocation();
                    }

                    addMember(MemberShape.builder()
                            .id(getId().withMember(member.getMemberName()))
                            .target(member.getTarget())
                            .addTraits(member.getAllTraits().values())
                            .addTraits(localTraits)
                            .source(location)
                            .build());
                }
            }

            return super.flattenMixins();
        }
Sets the value member of the map.

@param target Target of the member.
@param memberUpdater Consumer that can updated the created member shape.
@return Returns the builder.
smithy-model/src/main/java/software/amazon/smithy/model/shapes/MapShape.java