skeletons

24 files changed, 499 insertions, 0 deletions

diff --git a/src/act4e_solutions/intro.py b/src/act4e_solutions/intro.py
new file mode 100644
index 0000000..4d8207f
--- /dev/null
+++ b/src/act4e_solutions/intro.py
@@ -0,0 +1,6 @@
+import act4e_interfaces as I
+
+
+class MySimpleIntro(I.SimpleIntro):
+    def sum(self, a: int, b: int) -> int:
+        raise NotImplementedError()
diff --git a/src/act4e_solutions/maps.py b/src/act4e_solutions/maps.py
new file mode 100644
index 0000000..cf4e98f
--- /dev/null
+++ b/src/act4e_solutions/maps.py
@@ -0,0 +1,26 @@
+from typing import overload, TypeVar
+
+import act4e_interfaces as I
+
+A = TypeVar("A")
+B = TypeVar("B")
+C = TypeVar("C")
+
+
+class MyFiniteMapOperations(I.FiniteMapOperations):
+    @overload
+    def identity(self, s: I.FiniteSet[A]) -> I.FiniteMap[A, A]:
+        ...
+
+    @overload
+    def identity(self, s: I.Setoid[A]) -> I.Mapping[A, A]:
+        ...
+
+    def identity(self, s: I.Setoid[A]) -> I.Mapping[A, A]:
+        raise NotImplementedError()
+
+    def compose(self, f: I.FiniteMap[A, B], g: I.FiniteMap[B, C]) -> I.FiniteMap[A, C]:
+        raise NotImplementedError()
+
+    def as_relation(self, f: I.FiniteMap[A, B]) -> I.FiniteRelation[A, B]:
+        raise NotImplementedError()
diff --git a/src/act4e_solutions/maps_representation.py b/src/act4e_solutions/maps_representation.py
new file mode 100644
index 0000000..b77ef06
--- /dev/null
+++ b/src/act4e_solutions/maps_representation.py
@@ -0,0 +1,17 @@
+from typing import Any, TypeVar
+
+import act4e_interfaces as I
+
+__all__ = ["MyFiniteMapRepresentation"]
+
+A = TypeVar("A")
+B = TypeVar("B")
+
+
+class MyFiniteMapRepresentation(I.FiniteMapRepresentation):
+
+    def load(self, h: I.IOHelper, s: I.FiniteMap_desc) -> I.FiniteMap[A, B]:
+        raise NotImplementedError()
+
+    def save(self, h: I.IOHelper, m: I.FiniteMap[Any, Any]) -> I.FiniteMap_desc:
+        raise NotImplementedError()
diff --git a/src/act4e_solutions/posets.py b/src/act4e_solutions/posets.py
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/src/act4e_solutions/posets.py
diff --git a/src/act4e_solutions/posets_bounds.py b/src/act4e_solutions/posets_bounds.py
new file mode 100644
index 0000000..d582e67
--- /dev/null
+++ b/src/act4e_solutions/posets_bounds.py
@@ -0,0 +1,76 @@
+from typing import Any, List, Optional, overload, TypeVar
+
+import act4e_interfaces as I
+
+E = TypeVar("E")
+X = TypeVar("X")
+
+__all__ = ["MyFinitePosetMeasurement"]
+
+
+class MyFinitePosetMeasurement(I.FinitePosetMeasurement):
+    def height(self, fp: I.FinitePoset[Any]) -> int:
+        raise NotImplementedError()
+
+    def width(self, fp: I.FinitePoset[Any]) -> int:
+        raise NotImplementedError()
+
+
+class MyFinitePosetConstructionOpposite(I.FinitePosetConstructionOpposite):
+    @overload
+    def opposite(self, p: I.FinitePoset[X]) -> I.FinitePoset[X]:
+        ...
+
+    @overload
+    def opposite(self, p: I.Poset[X]) -> I.Poset[X]:
+        ...
+
+    def opposite(self, m: I.Poset[X]) -> I.Poset[X]:
+        raise NotImplementedError()
+
+
+class MyFinitePosetSubsetProperties(I.FinitePosetSubsetProperties):
+    def is_chain(self, fp: I.FinitePoset[X], s: List[X]) -> bool:
+        raise NotImplementedError()
+
+    def is_antichain(self, fp: I.FinitePoset[X], s: List[X]) -> bool:
+        raise NotImplementedError()
+
+
+class MyFinitePosetSubsetProperties2(I.FinitePosetSubsetProperties2):
+
+    def is_lower_set(self, fp: I.FinitePoset[X], s: List[X]) -> bool:
+        raise NotImplementedError()
+
+    def is_upper_set(self, fp: I.FinitePoset[X], s: List[X]) -> bool:
+        raise NotImplementedError()
+
+
+class MyFinitePosetClosures(I.FinitePosetClosures):
+    def upper_closure(self, fp: I.FinitePoset[X], s: List[X]) -> List[X]:
+        raise NotImplementedError()
+
+    def lower_closure(self, fp: I.FinitePoset[X], s: List[X]) -> List[X]:
+        raise NotImplementedError()
+
+
+class MyFinitePosetInfSup(I.FinitePosetInfSup):
+    def lower_bounds(self, fp: I.FinitePoset[E], s: List[E]) -> List[E]:
+        raise NotImplementedError()
+
+    def upper_bounds(self, fp: I.FinitePoset[E], s: List[E]) -> List[E]:
+        raise NotImplementedError()
+
+    def infimum(self, fp: I.FinitePoset[E], s: List[E]) -> Optional[E]:
+        raise NotImplementedError()
+
+    def supremum(self, fp: I.FinitePoset[E], s: List[E]) -> Optional[E]:
+        raise NotImplementedError()
+
+
+class MyFinitePosetMinMax(I.FinitePosetMinMax):
+    def minimal(self, fp: I.FinitePoset[E], S: List[E]) -> List[E]:
+        raise NotImplementedError()
+
+    def maximal(self, fp: I.FinitePoset[E], S: List[E]) -> List[E]:
+        raise NotImplementedError()
diff --git a/src/act4e_solutions/posets_construction.py b/src/act4e_solutions/posets_construction.py
new file mode 100644
index 0000000..f7fb2ae
--- /dev/null
+++ b/src/act4e_solutions/posets_construction.py
@@ -0,0 +1,18 @@
+from typing import Any, overload, TypeVar
+
+import act4e_interfaces as I
+
+X = TypeVar("X")
+
+
+class MyPosetConstructionPower(I.PosetConstructionPower):
+    @overload
+    def powerposet(self, s: I.FiniteSet[X]) -> I.FinitePosetOfFiniteSubsets[X, Any]:
+        ...
+
+    @overload
+    def powerposet(self, s: I.Setoid[X]) -> I.PosetOfFiniteSubsets[X, Any]:
+        ...
+
+    def powerposet(self, s: I.Setoid[X]) -> I.PosetOfFiniteSubsets[X, Any]:
+        raise NotImplementedError()
diff --git a/src/act4e_solutions/posets_interval.py b/src/act4e_solutions/posets_interval.py
new file mode 100644
index 0000000..0553811
--- /dev/null
+++ b/src/act4e_solutions/posets_interval.py
@@ -0,0 +1,33 @@
+from typing import Any, overload, TypeVar
+
+import act4e_interfaces as I
+
+C = TypeVar("C")
+E = TypeVar("E")
+X = TypeVar("X")
+
+
+class MyFinitePosetConstructionTwisted(I.FinitePosetConstructionTwisted):
+    @overload
+    def twisted(self, s: I.FinitePoset[X]) -> I.FinitePosetOfIntervals[X, Any]:
+        ...
+
+    @overload
+    def twisted(self, s: I.Poset[X]) -> I.PosetOfIntervals[X, Any]:
+        ...
+
+    def twisted(self, s: I.Poset[X]) -> I.PosetOfIntervals[X, Any]:
+        raise NotImplementedError()
+
+
+class MyFinitePosetConstructionArrow(I.FinitePosetConstructionArrow):
+    @overload
+    def arrow(self, s: I.FinitePoset[X]) -> I.FinitePosetOfIntervals[X, Any]:
+        ...
+
+    @overload
+    def arrow(self, s: I.Poset[X]) -> I.PosetOfIntervals[X, Any]:
+        ...
+
+    def arrow(self, s: I.Poset[X]) -> I.PosetOfIntervals[X, Any]:
+        raise NotImplementedError()
diff --git a/src/act4e_solutions/posets_map.py b/src/act4e_solutions/posets_map.py
new file mode 100644
index 0000000..d2671bb
--- /dev/null
+++ b/src/act4e_solutions/posets_map.py
@@ -0,0 +1,15 @@
+from typing import TypeVar
+
+import act4e_interfaces as I
+
+A = TypeVar("A")
+B = TypeVar("B")
+X = TypeVar("X")
+
+
+class MyFiniteMonotoneMapProperties(I.FiniteMonotoneMapProperties):
+    def is_monotone(self, p1: I.FinitePoset[A], p2: I.FinitePoset[B], m: I.FiniteMap[A, B]) -> bool:
+        raise NotImplementedError()
+
+    def is_antitone(self, p1: I.FinitePoset[A], p2: I.FinitePoset[B], m: I.FiniteMap[A, B]) -> bool:
+        raise NotImplementedError()
diff --git a/src/act4e_solutions/posets_monoidal.py b/src/act4e_solutions/posets_monoidal.py
new file mode 100644
index 0000000..1c18ce6
--- /dev/null
+++ b/src/act4e_solutions/posets_monoidal.py
@@ -0,0 +1,12 @@
+from typing import TypeVar
+
+import act4e_interfaces as I
+
+A = TypeVar("A")
+B = TypeVar("B")
+X = TypeVar("X")
+
+
+class MyMonoidalPosetOperations(I.MonoidalPosetOperations):
+    def is_monoidal_poset(self, fp: I.FinitePoset[X], fm: I.FiniteMonoid[X]) -> bool:
+        raise NotImplementedError()
diff --git a/src/act4e_solutions/posets_product.py b/src/act4e_solutions/posets_product.py
new file mode 100644
index 0000000..035eabe
--- /dev/null
+++ b/src/act4e_solutions/posets_product.py
@@ -0,0 +1,10 @@
+from typing import Any, Sequence, TypeVar
+
+import act4e_interfaces as I
+
+X = TypeVar("X")
+
+
+class MyFinitePosetConstructionProduct(I.FinitePosetConstructionProduct):
+    def product(self, ps: Sequence[I.FinitePoset[X]]) -> I.FinitePosetProduct[X, Any]:
+        raise NotImplementedError()
diff --git a/src/act4e_solutions/posets_representation.py b/src/act4e_solutions/posets_representation.py
new file mode 100644
index 0000000..9bdca1f
--- /dev/null
+++ b/src/act4e_solutions/posets_representation.py
@@ -0,0 +1,12 @@
+from typing import Any
+
+import act4e_interfaces as I
+
+
+class MyFinitePosetRepresentation(I.FinitePosetRepresentation):
+
+    def load(self, h: I.IOHelper, s: I.FinitePoset_desc) -> I.FinitePoset[Any]:
+        raise NotImplementedError()
+
+    def save(self, h: I.IOHelper, p: I.FinitePoset[Any]) -> I.FinitePoset_desc:
+        raise NotImplementedError()
diff --git a/src/act4e_solutions/posets_sum.py b/src/act4e_solutions/posets_sum.py
new file mode 100644
index 0000000..a91b0a0
--- /dev/null
+++ b/src/act4e_solutions/posets_sum.py
@@ -0,0 +1,18 @@
+from typing import Any, overload, Sequence, TypeVar
+
+import act4e_interfaces as I
+
+X = TypeVar("X")
+
+
+class MyFinitePosetConstructionSum(I.FinitePosetConstructionSum):
+    @overload
+    def disjoint_union(self, ps: Sequence[I.FinitePoset[X]]) -> I.FinitePosetDisjointUnion[X, Any]:
+        ...
+
+    @overload
+    def disjoint_union(self, ps: Sequence[I.Poset[X]]) -> I.PosetDisjointUnion[X, Any]:
+        ...
+
+    def disjoint_union(self, ps: Sequence[I.Poset[X]]) -> I.PosetDisjointUnion[X, Any]:
+        raise NotImplementedError()
diff --git a/src/act4e_solutions/py.typed b/src/act4e_solutions/py.typed
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/src/act4e_solutions/py.typed
diff --git a/src/act4e_solutions/relations.py b/src/act4e_solutions/relations.py
new file mode 100644
index 0000000..47a7c3e
--- /dev/null
+++ b/src/act4e_solutions/relations.py
@@ -0,0 +1,61 @@
+from typing import Any, TypeVar
+
+import act4e_interfaces as I
+from act4e_interfaces import FiniteRelation
+
+E1 = TypeVar("E1")
+E2 = TypeVar("E2")
+E3 = TypeVar("E3")
+E = TypeVar("E")
+
+A = TypeVar("A")
+B = TypeVar("B")
+
+
+class MyFiniteRelationProperties(I.FiniteRelationProperties):
+    def is_surjective(self, fr: I.FiniteRelation[Any, Any]) -> bool:
+        raise NotImplementedError()
+
+    def is_defined_everywhere(self, fr: I.FiniteRelation[Any, Any]) -> bool:
+        raise NotImplementedError()
+
+    def is_injective(self, fr: I.FiniteRelation[Any, Any]) -> bool:
+        raise NotImplementedError()
+
+    def is_single_valued(self, fr: I.FiniteRelation[Any, Any]) -> bool:
+        raise NotImplementedError()
+
+
+class MyFiniteRelationOperations(I.FiniteRelationOperations):
+    def transpose(self, fr: I.FiniteRelation[A, B]) -> I.FiniteRelation[B, A]:
+        raise NotImplementedError()
+
+
+class MyFiniteEndorelationProperties(I.FiniteEndorelationProperties):
+    def is_reflexive(self, fr: I.FiniteRelation[Any, Any]) -> bool:
+        raise NotImplementedError()
+
+    def is_irreflexive(self, fr: I.FiniteRelation[Any, Any]) -> bool:
+        raise NotImplementedError()
+
+    def is_transitive(self, fr: I.FiniteRelation[Any, Any]) -> bool:
+        raise NotImplementedError()
+
+    def is_symmetric(self, fr: I.FiniteRelation[Any, Any]) -> bool:
+        raise NotImplementedError()
+
+    def is_antisymmetric(self, fr: I.FiniteRelation[Any, Any]) -> bool:
+        raise NotImplementedError()
+
+    def is_asymmetric(self, fr: I.FiniteRelation[Any, Any]) -> bool:
+        raise NotImplementedError()
+
+
+class MyFiniteEndorelationOperations(I.FiniteEndorelationOperations):
+    def transitive_closure(self, fr: I.FiniteRelation[E, E]) -> I.FiniteRelation[E, E]:
+        raise NotImplementedError()
+
+
+class MyFiniteRelationCompose(I.FiniteRelationCompose):
+    def compose(self, fr1: FiniteRelation[E1, E2], fr2: FiniteRelation[E2, E3]) -> I.FiniteRelation[E1, E3]:
+        raise NotImplementedError()
diff --git a/src/act4e_solutions/relations_representation.py b/src/act4e_solutions/relations_representation.py
new file mode 100644
index 0000000..e150534
--- /dev/null
+++ b/src/act4e_solutions/relations_representation.py
@@ -0,0 +1,15 @@
+from typing import TypeVar
+
+import act4e_interfaces as I
+
+A = TypeVar("A")
+B = TypeVar("B")
+
+
+class MyFiniteRelationRepresentation(I.FiniteRelationRepresentation):
+
+    def load(self, h: I.IOHelper, data: I.FiniteRelation_desc) -> I.FiniteRelation[A, B]:
+        raise NotImplementedError()
+
+    def save(self, h: I.IOHelper, f: I.FiniteRelation[A, B]) -> I.FiniteRelation_desc:
+        raise NotImplementedError()
diff --git a/src/act4e_solutions/semigroups.py b/src/act4e_solutions/semigroups.py
new file mode 100644
index 0000000..31ecd58
--- /dev/null
+++ b/src/act4e_solutions/semigroups.py
@@ -0,0 +1,10 @@
+from typing import List, TypeVar
+
+import act4e_interfaces as I
+
+C = TypeVar("C")
+
+
+class MyFiniteSemigroupConstruct(I.FiniteSemigroupConstruct):
+    def free(self, fs: I.FiniteSet[C]) -> I.FreeSemigroup[C, List[C]]:
+        raise NotImplementedError()
diff --git a/src/act4e_solutions/semigroups_representation.py b/src/act4e_solutions/semigroups_representation.py
new file mode 100644
index 0000000..5d90823
--- /dev/null
+++ b/src/act4e_solutions/semigroups_representation.py
@@ -0,0 +1,30 @@
+from typing import Any, TypeVar
+
+import act4e_interfaces as I
+
+X = TypeVar("X")
+
+
+class MyFiniteSemigroupRepresentation(I.FiniteSemigroupRepresentation):
+
+    def load(self, h: I.IOHelper, s: I.FiniteSemigroup_desc) -> I.FiniteSemigroup[Any]:
+        raise NotImplementedError()
+
+    def save(self, h: I.IOHelper, m: I.FiniteSemigroup[Any]) -> I.FiniteSemigroup_desc:
+        raise NotImplementedError()
+
+
+class MyFiniteMonoidRepresentation(I.FiniteMonoidRepresentation):
+    def load(self, h: I.IOHelper, s: I.FiniteMonoid_desc) -> I.FiniteMonoid[X]:
+        raise NotImplementedError()
+
+    def save(self, h: I.IOHelper, m: I.FiniteMonoid[Any]) -> I.FiniteMonoid_desc:
+        raise NotImplementedError()
+
+
+class MyFiniteGroupRepresentation(I.FiniteGroupRepresentation):
+    def load(self, h: I.IOHelper, s: I.FiniteGroup_desc) -> I.FiniteGroup[X]:
+        raise NotImplementedError()
+
+    def save(self, h: I.IOHelper, m: I.FiniteGroup[Any]) -> I.FiniteGroup_desc:
+        raise NotImplementedError()
diff --git a/src/act4e_solutions/sets.py b/src/act4e_solutions/sets.py
new file mode 100644
index 0000000..7cb4252
--- /dev/null
+++ b/src/act4e_solutions/sets.py
@@ -0,0 +1,14 @@
+from typing import Callable, TypeVar
+
+import act4e_interfaces as I
+
+X = TypeVar("X")
+
+
+class MyEnumerableSetsOperations(I.EnumerableSetsOperations):
+    def make_set_sequence(self, f: Callable[[int], X]) -> I.EnumerableSet[X]:
+        raise NotImplementedError()
+
+    def union_esets(self, a: I.EnumerableSet[X], b: I.EnumerableSet[X]) -> I.EnumerableSet[X]:
+        """Creates the union of two EnumerableSet."""
+        raise NotImplementedError()
diff --git a/src/act4e_solutions/sets_power.py b/src/act4e_solutions/sets_power.py
new file mode 100644
index 0000000..1f3c103
--- /dev/null
+++ b/src/act4e_solutions/sets_power.py
@@ -0,0 +1,18 @@
+from typing import Any, overload, TypeVar
+
+import act4e_interfaces as I
+
+X = TypeVar("X")
+
+
+class MyMakePowerSet(I.MakePowerSet):
+    @overload
+    def powerset(self, s: I.FiniteSet[X]) -> I.FiniteSetOfFiniteSubsets[X, Any]:
+        ...
+
+    @overload
+    def powerset(self, s: I.Setoid[X]) -> I.SetOfFiniteSubsets[X, Any]:
+        ...
+
+    def powerset(self, s: I.Setoid[X]) -> I.SetOfFiniteSubsets[X, Any]:
+        raise NotImplementedError()
diff --git a/src/act4e_solutions/sets_product.py b/src/act4e_solutions/sets_product.py
new file mode 100644
index 0000000..19661ca
--- /dev/null
+++ b/src/act4e_solutions/sets_product.py
@@ -0,0 +1,18 @@
+from typing import Any, overload, Sequence, TypeVar
+
+import act4e_interfaces as I
+
+X = TypeVar("X")
+
+
+class MyMakeSetProduct(I.MakeSetProduct):
+    @overload
+    def product(self, components: Sequence[I.FiniteSet[X]]) -> I.FiniteSetProduct[X, Any]:
+        ...
+
+    @overload
+    def product(self, components: Sequence[I.Setoid[X]]) -> I.SetProduct[X, Any]:
+        ...
+
+    def product(self, components: Sequence[I.Setoid[X]]) -> I.SetProduct[X, Any]:
+        raise NotImplementedError()
diff --git a/src/act4e_solutions/sets_properties.py b/src/act4e_solutions/sets_properties.py
new file mode 100644
index 0000000..ef9f291
--- /dev/null
+++ b/src/act4e_solutions/sets_properties.py
@@ -0,0 +1,30 @@
+from typing import Any, overload, Sequence, TypeVar
+
+import act4e_interfaces as I
+
+__all__ = ["MyMakeSetUnion", "MyMakeSetIntersection", "MyFiniteSetProperties"]
+
+X = TypeVar("X")
+
+
+class MyFiniteSetProperties(I.FiniteSetProperties):
+    def is_subset(self, a: I.FiniteSet[X], b: I.FiniteSet[X]) -> bool:
+        raise NotImplementedError()
+
+
+class MyMakeSetUnion(I.MakeSetUnion):
+    @overload
+    def union(self, components: Sequence[I.FiniteSet[X]]) -> I.FiniteSetUnion[X, Any]:
+        ...
+
+    @overload
+    def union(self, components: Sequence[I.EnumerableSet[X]]) -> I.EnumerableSetUnion[X, Any]:
+        ...
+
+    def union(self, components: Sequence[I.Setoid[X]]) -> I.SetUnion[X, Any]:
+        raise NotImplementedError()
+
+
+class MyMakeSetIntersection(I.MakeSetIntersection):
+    def intersection(self, components: Sequence[I.FiniteSet[X]]) -> I.FiniteSet[X]:
+        raise NotImplementedError()
diff --git a/src/act4e_solutions/sets_representation.py b/src/act4e_solutions/sets_representation.py
new file mode 100644
index 0000000..d8c56d7
--- /dev/null
+++ b/src/act4e_solutions/sets_representation.py
@@ -0,0 +1,13 @@
+from typing import Any
+
+import act4e_interfaces as I
+
+__all__ = ["MyFiniteSetRepresentation"]
+
+
+class MyFiniteSetRepresentation(I.FiniteSetRepresentation):
+    def load(self, h: I.IOHelper, data: I.FiniteSet_desc) -> I.FiniteSet[Any]:
+        raise NotImplementedError()
+
+    def save(self, h: I.IOHelper, f: I.FiniteSet[Any]) -> I.FiniteSet_desc:
+        raise NotImplementedError()
diff --git a/src/act4e_solutions/sets_sum.py b/src/act4e_solutions/sets_sum.py
new file mode 100644
index 0000000..54e0e95
--- /dev/null
+++ b/src/act4e_solutions/sets_sum.py
@@ -0,0 +1,19 @@
+from typing import Any, overload, Sequence, TypeVar
+
+import act4e_interfaces as I
+
+
+X = TypeVar("X")
+
+
+class MyMakeSetDisjointUnion(I.MakeSetDisjointUnion):
+    @overload
+    def disjoint_union(self, components: Sequence[I.FiniteSet[X]]) -> I.FiniteSetDisjointUnion[X, Any]:
+        ...
+
+    @overload
+    def disjoint_union(self, components: Sequence[I.Setoid[X]]) -> I.SetDisjointUnion[X, Any]:
+        ...
+
+    def disjoint_union(self, components: Sequence[I.Setoid[X]]) -> I.SetDisjointUnion[X, Any]:
+        raise NotImplementedError()
diff --git a/src/act4e_solutions/sets_union_inter.py b/src/act4e_solutions/sets_union_inter.py
new file mode 100644
index 0000000..72f9e64
--- /dev/null
+++ b/src/act4e_solutions/sets_union_inter.py
@@ -0,0 +1,28 @@
+from typing import Any, overload, Sequence, TypeVar
+
+import act4e_interfaces as I
+
+X = TypeVar("X")
+
+
+class MyMakeSetUnion(I.MakeSetUnion):
+    @overload
+    def union(self, components: Sequence[I.FiniteSet[X]]) -> I.FiniteSetUnion[X, Any]:
+        ...
+
+    @overload
+    def union(self, components: Sequence[I.EnumerableSet[X]]) -> I.EnumerableSetUnion[X, Any]:
+        ...
+
+    def union(self, components: Sequence[I.EnumerableSet[X]]) -> I.EnumerableSetUnion[X, Any]:
+        raise NotImplementedError()
+
+
+class MySetoidOperations(I.SetoidOperations):
+    @classmethod
+    def union_setoids(cls, a: I.Setoid[X], b: I.Setoid[X]) -> I.Setoid[X]:
+        raise NotImplementedError()
+
+    @classmethod
+    def intersection_setoids(cls, a: I.Setoid[X], b: I.Setoid[X]) -> I.Setoid[X]:
+        raise NotImplementedError()