gh-35689: cylint: remove unused imports in folders [s-z]*
    
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### 📚 Description

remove unused imports found by cython-lint in all folders from s* to z*

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URL: #35689
Reported by: Frédéric Chapoton
Reviewer(s): Travis Scrimshaw

Author: Release Manager

src/sage/matrix/matrix_space.py

@@ -39,7 +39,7 @@
 # Sage matrix imports see :trac:`34283`
 
 # Sage imports
-import sage.structure.coerce
+import sage.structure.coerce_actions
 from sage.structure.parent import Parent
 from sage.structure.unique_representation import UniqueRepresentation
 import sage.rings.integer as integer
@@ -1054,7 +1054,7 @@ def _get_action_(self, S, op, self_on_left):
                         return matrix_action.MatrixPolymapAction(self, S)
                     else:
                         # action of base ring
-                        return sage.structure.coerce.RightModuleAction(S, self)
+                        return sage.structure.coerce_actions.RightModuleAction(S, self)
                 else:
                     if is_MatrixSpace(S):
                         # matrix multiplications
@@ -1065,7 +1065,7 @@ def _get_action_(self, S, op, self_on_left):
                         return matrix_action.PolymapMatrixAction(self, S)
                     else:
                         # action of base ring
-                        return sage.structure.coerce.LeftModuleAction(S, self)
+                        return sage.structure.coerce_actions.LeftModuleAction(S, self)
         except TypeError:
             return None
 

src/sage/stats/time_series.pyx

@@ -36,19 +36,19 @@ AUTHOR:
 - William Stein
 """
 
-#*****************************************************************************
+# ****************************************************************************
 #       Copyright (C) 2008 William Stein <[email protected]>
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
 # the Free Software Foundation, either version 2 of the License, or
 # (at your option) any later version.
-#                  http://www.gnu.org/licenses/
-#*****************************************************************************
+#                  https://www.gnu.org/licenses/
+# ****************************************************************************
 
 cimport cython
 from cpython.bytes cimport PyBytes_FromStringAndSize, PyBytes_AsString
-from libc.math cimport exp, floor, log, pow, sqrt
+from libc.math cimport exp, log, pow, sqrt
 from libc.string cimport memcpy
 from cysignals.memory cimport sig_malloc, sig_free
 from sage.structure.richcmp cimport rich_to_bool

src/sage/structure/category_object.pyx

@@ -47,18 +47,17 @@ This example illustrates generators for a free module over `\ZZ`.
     ((1, 0, 0, 0), (0, 1, 0, 0), (0, 0, 1, 0), (0, 0, 0, 1))
 """
 
-#*****************************************************************************
+# ****************************************************************************
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
 # the Free Software Foundation, either version 2 of the License, or
 # (at your option) any later version.
-#                  http://www.gnu.org/licenses/
-#*****************************************************************************
+#                  https://www.gnu.org/licenses/
+# ****************************************************************************
 
 from sage.cpython.getattr import dir_with_other_class
 from sage.cpython.getattr cimport getattr_from_other_class
 from sage.categories.category import Category
-from sage.structure.debug_options cimport debug
 from sage.misc.cachefunc import cached_method
 from sage.structure.dynamic_class import DynamicMetaclass
 
@@ -668,15 +667,16 @@ cdef class CategoryObject(SageObject):
             sage: print(latex(f))
             5 x_{1}^{10} + x_{0}^{3}
         """
-        from sage.misc.latex import latex, latex_variable_name
+        from sage.misc.latex import latex_variable_name
         try:
             names = self._latex_names
             if names is not None:
                 return names
         except AttributeError:
             pass
         # Compute the latex versions of the variable names.
-        self._latex_names = [latex_variable_name(x) for x in self.variable_names()]
+        self._latex_names = [latex_variable_name(x)
+                             for x in self.variable_names()]
         return self._latex_names
 
     def latex_name(self):

src/sage/structure/coerce.pyx

@@ -64,36 +64,35 @@ For more information on how to specify coercions, conversions, and actions,
 see the documentation for :class:`Parent`.
 """
 
-#*****************************************************************************
+# ****************************************************************************
 #       Copyright (C) 2007 Robert Bradshaw <[email protected]>
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
 # the Free Software Foundation, either version 2 of the License, or
 # (at your option) any later version.
-#                  http://www.gnu.org/licenses/
-#*****************************************************************************
+#                  https://www.gnu.org/licenses/
+# ****************************************************************************
 
-from cpython.object cimport (PyObject, PyTypeObject,
-        PyObject_CallObject, PyObject_RichCompare, Py_TYPE,
-        Py_EQ, Py_NE, Py_LT, Py_LE, Py_GT, Py_GE)
+from cpython.object cimport (PyTypeObject, PyObject_CallObject,
+                             PyObject_RichCompare, Py_TYPE,
+                             Py_EQ, Py_NE, Py_LT, Py_LE, Py_GT)
 from cpython.weakref cimport PyWeakref_GET_OBJECT, PyWeakref_NewRef
 from libc.string cimport strncmp
 cimport gmpy2
 
-cdef add, mul, truediv
-from operator import add, mul, truediv
+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_actions import LeftModuleAction, RightModuleAction
 from .coerce_exceptions import CoercionException
 from sage.rings.integer_fake cimport is_Integer
 from sage.categories.map cimport Map
 from sage.categories.morphism import IdentityMorphism
-from sage.categories.action cimport Action, InverseAction, PrecomposedAction
+from sage.categories.action cimport Action, PrecomposedAction
 from sage.sets.pythonclass cimport Set_PythonType
 
 import traceback
@@ -1653,7 +1652,6 @@ cdef class CoercionModel:
             sage: print(cm.discover_coercion(QQ, QQ^3))
             None
         """
-        from sage.categories.homset import Hom
         if R is S:
             return None, None
 

src/sage/structure/element.pyx

@@ -290,15 +290,11 @@ continue down the MRO and find the ``_add_`` method in the category.
 
 cimport cython
 from cpython cimport *
-from cpython.ref cimport PyObject
 
 from sage.ext.stdsage cimport *
 
-import types
 cdef add, sub, mul, truediv, floordiv, mod, matmul, pow
-cdef iadd, isub, imul, itruediv, ifloordiv, imod, ipow
-from operator import (add, sub, mul, truediv, floordiv, mod, matmul, pow,
-                      iadd, isub, imul, itruediv, ifloordiv, imod, imatmul, ipow)
+from operator import (add, sub, mul, truediv, floordiv, mod, matmul, pow)
 
 cdef dict _coerce_op_symbols = dict(
         add='+', sub='-', mul='*', truediv='/', floordiv='//', mod='%', matmul='@', pow='^',
@@ -310,8 +306,6 @@ from sage.structure.parent cimport Parent
 from sage.cpython.type cimport can_assign_class
 from sage.cpython.getattr cimport getattr_from_other_class
 from sage.misc.lazy_format import LazyFormat
-from sage.misc import sageinspect
-from sage.misc.classcall_metaclass cimport ClasscallMetaclass
 from sage.arith.long cimport integer_check_long_py
 from sage.arith.power cimport generic_power as arith_generic_power
 from sage.arith.numerical_approx cimport digits_to_bits
@@ -711,7 +705,6 @@ cdef class Element(SageObject):
             ...
             AssertionError: self.an_element() is not in self
         """
-        from sage.categories.objects    import Objects
         tester = self._tester(**options)
         SageObject._test_category(self, tester = tester)
         category = self.category()

src/sage/structure/formal_sum.py

@@ -49,7 +49,7 @@
     True
 """
 
-#*****************************************************************************
+# ****************************************************************************
 #       Copyright (C) 2004 William Stein <[email protected]>
 #
 #  Distributed under the terms of the GNU General Public License (GPL)
@@ -61,8 +61,8 @@
 #
 #  The full text of the GPL is available at:
 #
-#                  http://www.gnu.org/licenses/
-#*****************************************************************************
+#                  https://www.gnu.org/licenses/
+# ****************************************************************************
 
 from sage.misc.repr import repr_lincomb
 import operator
@@ -73,7 +73,7 @@
 from sage.structure.richcmp import richcmp
 from sage.rings.integer_ring import ZZ
 from sage.structure.parent import Parent
-from sage.structure.coerce import LeftModuleAction, RightModuleAction
+from sage.structure.coerce_actions import LeftModuleAction, RightModuleAction
 from sage.categories.action import PrecomposedAction
 from sage.structure.unique_representation import UniqueRepresentation
 

src/sage/structure/parent.pyx

@@ -103,23 +103,22 @@ This came up in some subtle bug once::
 #                  https://www.gnu.org/licenses/
 # ****************************************************************************
 
-from cpython.object cimport PyObject, Py_NE, Py_EQ, Py_LE, Py_GE
+from cpython.object cimport Py_EQ, Py_LE, Py_GE
 from cpython.bool cimport *
 
 from types import MethodType, BuiltinMethodType
 import operator
 from copy import copy
 
 from sage.cpython.type cimport can_assign_class
-cimport sage.categories.morphism as morphism
 cimport sage.categories.map as map
 from sage.structure.debug_options cimport debug
 from sage.structure.sage_object cimport SageObject
 from sage.misc.cachefunc import cached_method
 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, Set_PythonType
+from sage.sets.pythonclass cimport Set_PythonType_class
 from .category_object import CategoryObject
 from .coerce cimport coercion_model
 from .coerce cimport parent_is_integers
@@ -2599,7 +2598,6 @@ cdef class Parent(sage.structure.category_object.CategoryObject):
         # If needed, it will be passed to Left/RightModuleAction.
         from sage.categories.action import Action, PrecomposedAction
         from sage.categories.homset import Hom
-        from .coerce_actions import LeftModuleAction, RightModuleAction
         cdef Parent R
 
         for action in self._action_list:

src/sage/symbolic/ring.pyx

@@ -205,22 +205,14 @@ cdef class SymbolicRing(sage.rings.abc.SymbolicRing):
 
             return False
         else:
-            from sage.rings.real_mpfr import mpfr_prec_min
-
             from sage.rings.fraction_field import is_FractionField
-            from sage.rings.real_mpfi import is_RealIntervalField
-            from sage.rings.real_arb import RealBallField
-            from sage.rings.complex_arb import ComplexBallField
             from sage.rings.polynomial.polynomial_ring import is_PolynomialRing
             from sage.rings.polynomial.multi_polynomial_ring import is_MPolynomialRing
             from sage.rings.polynomial.laurent_polynomial_ring_base import LaurentPolynomialRing_generic
-            from sage.rings.complex_mpfr import ComplexField
             from sage.rings.infinity import InfinityRing, UnsignedInfinityRing
             from sage.rings.real_lazy import RLF, CLF
             from sage.rings.finite_rings.finite_field_base import FiniteField
 
-            from sage.interfaces.maxima import Maxima
-
             from .subring import GenericSymbolicSubring
 
             if R._is_numerical():