gh-35675: cylint: remove unused imports in matrix folder
    
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### 📚 Description

remove all unused imports in pyx files in the `matrix` folder

found using `cython-lint`

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- [ ] I have created tests covering the changes.
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### ⌛ Dependencies

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URL: #35675
Reported by: Frédéric Chapoton
Reviewer(s): Matthias Köppe

Author: Release Manager

src/sage/matrix/matrix0.pyx

@@ -30,13 +30,11 @@ import sage.misc.latex
 import sage.rings.integer
 
 from sage.arith.power cimport generic_power
-from sage.misc.verbose import verbose, get_verbose
 from sage.structure.sequence import Sequence
 from sage.structure.parent cimport Parent
 
 cimport sage.structure.element
-from sage.structure.element cimport ModuleElement, Element, RingElement, Vector
-from sage.structure.mutability cimport Mutability
+from sage.structure.element cimport Element, Vector
 from sage.misc.misc_c cimport normalize_index
 
 from sage.categories.fields import Fields

src/sage/matrix/matrix2.pyx

@@ -80,19 +80,18 @@ from cpython cimport *
 from cysignals.signals cimport sig_check
 
 from sage.misc.lazy_string import lazy_string
-from sage.misc.randstate cimport randstate, current_randstate
+from sage.misc.randstate cimport current_randstate
 from sage.structure.coerce cimport py_scalar_parent
 from sage.structure.sequence import Sequence
 from sage.structure.coerce cimport coercion_model
 from sage.structure.element import is_Vector
 from sage.structure.element cimport have_same_parent
-from sage.misc.verbose import verbose, get_verbose
+from sage.misc.verbose import verbose
 from sage.categories.fields import Fields
 from sage.categories.integral_domains import IntegralDomains
 from sage.rings.ring import is_Ring
 from sage.rings.number_field.number_field_base import NumberField
 from sage.rings.integer_ring import ZZ, is_IntegerRing
-from sage.rings.integer import Integer
 from sage.rings.rational_field import QQ, is_RationalField
 import sage.rings.abc
 from sage.arith.numerical_approx cimport digits_to_bits

src/sage/matrix/matrix_cyclo_dense.pyx

@@ -47,13 +47,13 @@ from cysignals.signals cimport sig_on, sig_off
 
 include "sage/libs/ntl/decl.pxi"
 
-from sage.structure.element cimport ModuleElement, RingElement, Element, Vector
+from sage.structure.element cimport Element
 from sage.misc.randstate cimport randstate, current_randstate
 from sage.libs.gmp.randomize cimport *
 
 from sage.libs.flint.types cimport fmpz_t, fmpq
-from sage.libs.flint.fmpz cimport fmpz_init, fmpz_clear, fmpz_set, fmpz_set_mpz, fmpz_one, fmpz_get_mpz, fmpz_add, fmpz_mul, fmpz_sub, fmpz_mul_si, fmpz_mul_si, fmpz_mul_si, fmpz_divexact, fmpz_lcm
-from sage.libs.flint.fmpq cimport fmpq_is_zero, fmpq_get_mpq, fmpq_set_mpq, fmpq_canonicalise
+from sage.libs.flint.fmpz cimport fmpz_init, fmpz_clear, fmpz_set_mpz, fmpz_one, fmpz_get_mpz, fmpz_add, fmpz_mul, fmpz_sub, fmpz_mul_si, fmpz_mul_si, fmpz_mul_si, fmpz_divexact, fmpz_lcm
+from sage.libs.flint.fmpq cimport fmpq_is_zero, fmpq_set_mpq, fmpq_canonicalise
 from sage.libs.flint.fmpq_mat cimport fmpq_mat_entry_num, fmpq_mat_entry_den, fmpq_mat_entry
 
 from .args cimport MatrixArgs_init
@@ -70,14 +70,12 @@ from sage.rings.rational_field import QQ
 from sage.rings.integer_ring import ZZ
 from sage.rings.real_mpfr import create_RealNumber as RealNumber
 from sage.rings.integer cimport Integer
-from sage.rings.rational cimport Rational
 from sage.rings.polynomial.polynomial_ring_constructor import PolynomialRing
 from sage.rings.number_field.number_field_element cimport NumberFieldElement
 from sage.rings.number_field.number_field_element_quadratic cimport NumberFieldElement_quadratic
 
 from sage.structure.proof.proof import get_flag as get_proof_flag
 from sage.misc.verbose import verbose
-import math
 
 from sage.matrix.matrix_modn_dense_double import MAX_MODULUS as MAX_MODULUS_modn_dense_double
 from sage.arith.multi_modular import MAX_MODULUS as MAX_MODULUS_multi_modular

src/sage/matrix/matrix_dense.pyx

@@ -10,7 +10,6 @@ TESTS::
 
 cimport sage.matrix.matrix as matrix
 
-from sage.structure.element cimport Element, RingElement
 from sage.structure.richcmp cimport richcmp_item, rich_to_bool
 import sage.matrix.matrix_space
 import sage.structure.sequence

src/sage/matrix/matrix_gap.pyx

@@ -12,7 +12,6 @@ Wrappers on GAP matrices
 # ****************************************************************************
 
 from sage.libs.gap.libgap import libgap
-from . import matrix_space
 from sage.structure.element cimport Matrix
 from .args cimport MatrixArgs_init
 

src/sage/matrix/matrix_generic_sparse.pyx

@@ -52,14 +52,10 @@ EXAMPLES::
     sage: c.is_sparse()
     True
 """
-
-cimport sage.matrix.matrix as matrix
 cimport sage.matrix.matrix_sparse as matrix_sparse
 cimport sage.structure.element
-from sage.structure.element cimport ModuleElement
 from .args cimport MatrixArgs_init
 
-import sage.misc.misc as misc
 
 cdef class Matrix_generic_sparse(matrix_sparse.Matrix_sparse):
     r"""

src/sage/matrix/matrix_gf2e_dense.pyx

@@ -83,11 +83,11 @@ REFERENCES:
 #                  https://www.gnu.org/licenses/
 #*****************************************************************************
 
-from cysignals.signals cimport sig_check, sig_on, sig_off
+from cysignals.signals cimport sig_on, sig_off
 
 cimport sage.matrix.matrix_dense as matrix_dense
-from sage.structure.element cimport Matrix, Vector
-from sage.structure.element cimport ModuleElement, Element, RingElement
+from sage.structure.element cimport Matrix
+from sage.structure.element cimport Element
 from sage.structure.richcmp cimport rich_to_bool
 from sage.rings.finite_rings.element_base cimport Cache_base
 
@@ -97,7 +97,7 @@ from sage.misc.randstate cimport randstate, current_randstate
 from sage.matrix.matrix_mod2_dense cimport Matrix_mod2_dense
 from .args cimport SparseEntry, MatrixArgs_init
 
-from sage.libs.m4ri cimport m4ri_word, mzd_copy, mzd_init
+from sage.libs.m4ri cimport m4ri_word, mzd_copy
 from sage.libs.m4rie cimport *
 from sage.libs.m4rie cimport mzed_t
 

src/sage/matrix/matrix_gfpn_dense.pyx

@@ -34,14 +34,11 @@ AUTHORS:
 # (at your option) any later version.
 #                  https://www.gnu.org/licenses/
 # ***************************************************************************
-
 from cysignals.memory cimport check_realloc, check_malloc, sig_free
 from cpython.bytes cimport PyBytes_AsString, PyBytes_FromStringAndSize
 from cysignals.signals cimport sig_on, sig_off, sig_check
 cimport cython
 
-import os
-
 ####################
 #
 # import sage types
@@ -53,12 +50,10 @@ from sage.cpython.string import FS_ENCODING
 from sage.rings.integer import Integer
 from sage.rings.finite_rings.finite_field_constructor import GF
 from sage.rings.finite_rings.integer_mod import IntegerMod_int
-from sage.matrix.constructor import random_matrix
 from sage.matrix.matrix_space import MatrixSpace
 from sage.misc.randstate import current_randstate
 from sage.misc.randstate cimport randstate
-from sage.misc.cachefunc import cached_method, cached_function
-from sage.structure.element cimport Element, ModuleElement, RingElement, Matrix
+from sage.structure.element cimport Element, Matrix
 from sage.structure.richcmp import rich_to_bool
 from .args cimport MatrixArgs_init
 

src/sage/matrix/matrix_integer_dense.pyx

@@ -86,7 +86,6 @@ from sage.structure.proof.proof import get_flag as get_proof_flag
 from sage.structure.richcmp cimport rich_to_bool
 from sage.misc.randstate cimport randstate, current_randstate
 
-from sage.matrix.matrix_rational_dense cimport Matrix_rational_dense
 from .args cimport SparseEntry, MatrixArgs_init
 
 #########################################################
@@ -114,7 +113,6 @@ from sage.rings.polynomial.polynomial_ring_constructor import PolynomialRing
 from sage.rings.polynomial.polynomial_integer_dense_flint cimport Polynomial_integer_dense_flint
 from sage.structure.element cimport Element, Vector
 from sage.structure.element import is_Vector
-from sage.structure.sequence import Sequence
 
 from .matrix_modn_dense_float cimport Matrix_modn_dense_template
 from .matrix_modn_dense_float cimport Matrix_modn_dense_float

src/sage/matrix/matrix_integer_sparse.pyx

@@ -62,7 +62,7 @@ from sage.libs.flint.fmpz_poly cimport fmpz_poly_fit_length, fmpz_poly_set_coeff
 from sage.libs.flint.fmpz_mat cimport fmpz_mat_entry
 
 from .matrix_modn_sparse cimport Matrix_modn_sparse
-from sage.structure.element cimport ModuleElement, RingElement, Element, Vector
+from sage.structure.element cimport Element
 
 import sage.matrix.matrix_space as matrix_space