gh-36573: Replace relative imports by absolute ones in structure
    
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Relative imports are not used consistently in the codebase and result in
issues for doctesting with pytest (which admittedly is a limitation of
pytest). We normalize the relative imports in `sage.structure` to be
absolute imports.

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URL: #36573
Reported by: Tobias Diez
Reviewer(s):

Author: Release Manager

src/sage/structure/all.py

@@ -1,29 +1,29 @@
-from .factorization import Factorization
+from sage.structure.factorization import Factorization
 
-from .sequence import Sequence, seq
+from sage.structure.sequence import Sequence, seq
 
-from .unique_representation import UniqueRepresentation
+from sage.structure.unique_representation import UniqueRepresentation
 
-from .sage_object import SageObject
+from sage.structure.sage_object import SageObject
 
-from .element import (
+from sage.structure.element import (
     canonical_coercion,
     coercion_model,
     get_coercion_model,
     coercion_traceback,
     parent
     )
 
-from .parent import Parent
+from sage.structure.parent import Parent
 
-from .parent_gens import localvars
+from sage.structure.parent_gens import localvars
 
-from .proof import all as proof
+from sage.structure.proof import all as proof
 
 from sage.misc.lazy_import import lazy_import
 lazy_import('sage.structure.formal_sum', ['FormalSums', 'FormalSum'])
 del lazy_import
 
-from .mutability import Mutability
+from sage.structure.mutability import Mutability
 
-from .element_wrapper import ElementWrapper
+from sage.structure.element_wrapper import ElementWrapper

src/sage/structure/coerce.pxd

@@ -1,5 +1,5 @@
-from .parent cimport Parent
-from .coerce_dict cimport TripleDict
+from sage.structure.parent cimport Parent
+from sage.structure.coerce_dict cimport TripleDict
 
 cpdef py_scalar_parent(py_type) noexcept
 cpdef py_scalar_to_element(py) noexcept

src/sage/structure/coerce.pyx

@@ -84,11 +84,11 @@ cimport gmpy2
 cdef mul, truediv
 from operator import mul, truediv
 
-from .richcmp cimport rich_to_bool, revop
-from .sage_object cimport SageObject
-from .parent cimport Parent_richcmp_element_without_coercion
-from .element cimport bin_op_exception, parent, Element
-from .coerce_exceptions import CoercionException
+from sage.structure.richcmp cimport rich_to_bool, revop
+from sage.structure.sage_object cimport SageObject
+from sage.structure.parent cimport Parent_richcmp_element_without_coercion
+from sage.structure.element cimport bin_op_exception, parent, Element
+from sage.structure.coerce_exceptions import CoercionException
 from sage.rings.integer_fake cimport is_Integer
 from sage.categories.map cimport Map
 from sage.categories.morphism import IdentityMorphism

src/sage/structure/coerce_actions.pyx

@@ -18,10 +18,10 @@ from cpython.long cimport *
 from cpython.number cimport *
 from cysignals.signals cimport sig_check
 
-from .coerce cimport coercion_model
-from .element cimport parent, Element, ModuleElement
-from .parent cimport Parent
-from .coerce_exceptions import CoercionException
+from sage.structure.coerce cimport coercion_model
+from sage.structure.element cimport parent, Element, ModuleElement
+from sage.structure.parent cimport Parent
+from sage.structure.coerce_exceptions import CoercionException
 from sage.categories.action cimport InverseAction, PrecomposedAction
 from sage.arith.long cimport integer_check_long
 

src/sage/structure/element.pxd

@@ -1,5 +1,5 @@
-from .sage_object cimport SageObject
-from .parent cimport Parent
+from sage.structure.sage_object cimport SageObject
+from sage.structure.parent cimport Parent
 from sage.misc.inherit_comparison cimport InheritComparisonMetaclass
 
 

src/sage/structure/factory.pyx

@@ -56,7 +56,7 @@ AUTHORS:
 
 import types
 
-from .sage_object cimport SageObject
+from sage.structure.sage_object cimport SageObject
 
 cdef sage_version
 from sage.version import version as sage_version

src/sage/structure/parent.pyx

@@ -119,13 +119,13 @@ from sage.misc.lazy_attribute import lazy_attribute
 from sage.categories.sets_cat import Sets, EmptySetError
 from sage.misc.lazy_string cimport _LazyString
 from sage.sets.pythonclass cimport Set_PythonType_class
-from .category_object import CategoryObject
-from .coerce cimport coercion_model
-from .coerce cimport parent_is_integers
-from .coerce_exceptions import CoercionException
-from .coerce_maps cimport (NamedConvertMap, DefaultConvertMap,
+from sage.structure.category_object import CategoryObject
+from sage.structure.coerce cimport coercion_model
+from sage.structure.coerce cimport parent_is_integers
+from sage.structure.coerce_exceptions import CoercionException
+from sage.structure.coerce_maps cimport (NamedConvertMap, DefaultConvertMap,
                            DefaultConvertMap_unique, CallableConvertMap)
-from .element cimport parent
+from sage.structure.element cimport parent
 
 
 cdef _record_exception() noexcept:

src/sage/structure/parent_base.pxd

@@ -6,7 +6,7 @@
 #                  https://www.gnu.org/licenses/
 ###############################################################################
 
-from .parent_old cimport Parent as Parent_old
+from sage.structure.parent_old cimport Parent as Parent_old
 
 cdef class ParentWithBase(Parent_old):
     pass

src/sage/structure/parent_base.pyx

@@ -12,7 +12,7 @@ Base class for old-style parent objects with a base ring
 # ****************************************************************************
 
 cimport sage.structure.parent as parent
-from .coerce_exceptions import CoercionException
+from sage.structure.coerce_exceptions import CoercionException
 
 cdef inline check_old_coerce(parent.Parent p) noexcept:
     if p._element_constructor is not None:

src/sage/structure/parent_gens.pxd

@@ -12,7 +12,7 @@ Parent objects with generators
 #                  http://www.gnu.org/licenses/
 #*****************************************************************************
 
-from .parent_base cimport ParentWithBase
+from sage.structure.parent_base cimport ParentWithBase
 
 
 cdef class ParentWithGens(ParentWithBase):