gh-37722: Remove `CombinatorialClass`
    
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- Fixes #36133
- Fixes #33384
- Fixes #19474
- Fixes #12913

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### ⌛ Dependencies

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URL: #37722
Reported by: Matthias Köppe
Reviewer(s): Martin Rubey, Matthias Köppe, Travis Scrimshaw

Author: Release Manager

src/sage/categories/enumerated_sets.py

@@ -990,8 +990,12 @@ def map(self, f, name=None, *, is_injective=True):
                 ....:                        '_test_enumerated_set_contains',
                 ....:                        '_test_some_elements'])
             """
-            from sage.combinat.combinat import MapCombinatorialClass
-            return MapCombinatorialClass(self, f, name, is_injective=is_injective)
+            from sage.sets.image_set import ImageSubobject
+
+            image = ImageSubobject(f, self, is_injective=is_injective)
+            if name:
+                image.rename(name)
+            return image
 
 #
 #  Consistency test suite for an enumerated set:

src/sage/combinat/all.py

@@ -56,8 +56,7 @@
 
 from sage.misc.lazy_import import lazy_import
 
-from .combinat import (CombinatorialClass, CombinatorialObject,
-                       MapCombinatorialClass,
+from .combinat import (CombinatorialObject,
                        bell_number, bell_polynomial, bernoulli_polynomial,
                        catalan_number, euler_number,
                        fibonacci, fibonacci_sequence, fibonacci_xrange,
@@ -66,12 +65,6 @@
                        polygonal_number, stirling_number1, stirling_number2,
                        tuples, unordered_tuples)
 
-lazy_import('sage.combinat.combinat',
-            ('InfiniteAbstractCombinatorialClass', 'UnionCombinatorialClass',
-             'FilteredCombinatorialClass'),
-            deprecation=(31545, 'this class is deprecated, do not use'))
-
-
 from .expnums import expnums
 
 from sage.combinat.chas.all import *

src/sage/combinat/cartesian_product.py

@@ -112,6 +112,16 @@ def iterfunc():
                                            category=category,
                                            cache=False)
 
+    def __hash__(self):
+        r"""
+        EXAMPLES::
+
+            sage: from sage.combinat.cartesian_product import CartesianProduct_iters
+            sage: cp = CartesianProduct_iters((1,2), (3,4))
+            sage: hash(cp) == CartesianProduct_iters((1,2), (3,4))
+        """
+        return hash(tuple(self.iters))
+
     def __contains__(self, x):
         """
         EXAMPLES::