gh-37420: Remove long/int relic
    
in py2, long and int were different types. In py3, only int remains,
with long a synonym in cython.

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URL: #37420
Reported by: nbruin
Reviewer(s): grhkm21

Author: Release Manager

src/sage/rings/integer.pxd

@@ -42,6 +42,3 @@ cdef inline Integer _Integer_from_mpz(mpz_t e) noexcept:
     cdef Integer z = Integer.__new__(Integer)
     mpz_set(z.value, e)
     return z
-
-cdef class int_to_Z(Morphism):
-    pass

src/sage/rings/integer.pyx

@@ -7424,87 +7424,6 @@ def make_integer(s):
 
 
 cdef class int_to_Z(Morphism):
-    """
-    Morphism from Python ints to Sage integers.
-
-    EXAMPLES::
-
-        sage: f = ZZ.coerce_map_from(int)
-        sage: type(f)
-        <class 'sage.rings.integer.long_to_Z'>
-        sage: f(5r)
-        5
-        sage: type(f(5r))
-        <class 'sage.rings.integer.Integer'>
-        sage: 1 + 2r
-        3
-        sage: type(1 + 2r)
-        <class 'sage.rings.integer.Integer'>
-
-    This is intended for internal use by the coercion system,
-    to facilitate fast expressions mixing ints and more complex
-    Python types.  Note that (as with all morphisms) the input
-    is forcably coerced to the domain ``int`` if it is not
-    already of the correct type which may have undesirable results::
-
-        sage: f.domain()
-        Set of Python objects of class 'int'
-        sage: f(1/3)
-        0
-        sage: f(1.7)
-        1
-        sage: f("10")
-        10
-
-    A pool is used for small integers::
-
-        sage: f(10) is f(10)
-        True
-        sage: f(-2) is f(-2)
-        True
-    """
-
-    def __init__(self):
-        """
-        TESTS::
-
-            sage: f = ZZ.coerce_map_from(int)
-            sage: f.parent()
-            Set of Morphisms from Set of Python objects of class 'int' to Integer Ring in Category of sets
-        """
-        import sage.categories.homset
-        from sage.sets.pythonclass import Set_PythonType
-        Morphism.__init__(self, sage.categories.homset.Hom(Set_PythonType(int), integer_ring.ZZ))
-
-    cpdef Element _call_(self, a) noexcept:
-        """
-        Return a new integer with the same value as ``a``.
-
-        TESTS::
-
-            sage: f = ZZ.coerce_map_from(int)
-            sage: f(100r)
-            100
-        """
-        if type(a) is not int:
-            raise TypeError("must be a Python int object")
-
-        return smallInteger(PyLong_AsLong(a))
-
-    def _repr_type(self):
-        """
-        TESTS::
-
-            sage: f = ZZ.coerce_map_from(int)
-            sage: print(f)
-            Native morphism:
-              From: Set of Python objects of class 'int'
-              To:   Integer Ring
-        """
-        return "Native"
-
-
-cdef class long_to_Z(Morphism):
     """
     EXAMPLES::
 

src/sage/rings/integer_ring.pyx

@@ -586,9 +586,7 @@ cdef class IntegerRing_class(PrincipalIdealDomain):
             sage: f(-7r)
             -7
         """
-        if S is long:
-            return sage.rings.integer.long_to_Z()
-        elif S is int:
+        if S is int:
             return sage.rings.integer.int_to_Z()
         elif S is bool:
             return True