cython-linting of unused imports in modules and dynamics

src/sage/dynamics/arithmetic_dynamics/projective_ds_helper.pyx

@@ -9,21 +9,21 @@ AUTHORS:
 
 """
 
-#*****************************************************************************
+# ****************************************************************************
 #       Copyright (C) 2014 William Stein <wstein@gmail.com>
 #
 # 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.arith.functions cimport LCM_list
 from sage.rings.finite_rings.finite_field_constructor import GF
-from sage.sets.set import Set
 from sage.misc.misc import subsets
 
+
 cpdef _fast_possible_periods(self, return_points=False):
     r"""
     Return the list of possible minimal periods of a periodic point

src/sage/dynamics/complex_dynamics/mandel_julia_helper.pyx

@@ -9,24 +9,22 @@ AUTHORS:
 - Ben Barros
 
 """
-
-#*****************************************************************************
+# ****************************************************************************
 #       Copyright (C) 2017 BEN BARROS <bbarros@slu.edu>
 #
 # 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.plot.colors import Color
 from sage.repl.image import Image
 from copy import copy
 from cysignals.signals cimport sig_check
 from sage.rings.complex_mpfr import ComplexField
-from sage.functions.log import exp, log
-from sage.symbolic.constants import pi
+from sage.functions.log import exp
 from sage.symbolic.relation import solve
 from sage.rings.polynomial.polynomial_ring_constructor import PolynomialRing
 from sage.rings.cc import CC

src/sage/modules/free_module_element.pyx

@@ -124,7 +124,6 @@ from sage.rings.infinity import Infinity, AnInfinity
 from sage.rings.integer_ring import ZZ
 from sage.rings.abc import RealDoubleField, ComplexDoubleField
 
-from sage.rings.ring cimport Ring
 from sage.rings.integer cimport Integer, smallInteger
 from sage.arith.numerical_approx cimport digits_to_bits
 

src/sage/modules/vector_integer_dense.pyx

@@ -62,8 +62,6 @@ from sage.rings.integer cimport Integer, _Integer_from_mpz
 
 cimport sage.modules.free_module_element as free_module_element
 
-from .free_module_element import vector
-
 from sage.libs.gmp.mpz cimport *
 
 cdef class Vector_integer_dense(free_module_element.FreeModuleElement):

src/sage/modules/vector_mod2_dense.pyx

@@ -46,7 +46,6 @@ from sage.rings.rational cimport Rational
 from sage.structure.element cimport Element, Vector
 from sage.structure.richcmp cimport rich_to_bool
 cimport sage.modules.free_module_element as free_module_element
-from .free_module_element import vector
 
 from sage.libs.m4ri cimport *
 

src/sage/modules/vector_modn_dense.pyx

@@ -131,7 +131,7 @@ cdef mod_int ivalue(IntegerMod_abstract x) except -1:
 from sage.structure.element cimport Element, Vector
 
 cimport sage.modules.free_module_element as free_module_element
-from .free_module_element import vector
+
 
 cdef class Vector_modn_dense(free_module_element.FreeModuleElement):
     cdef _new_c(self):

src/sage/modules/vector_rational_dense.pyx

@@ -44,26 +44,25 @@ TESTS::
     True
 """
 
-#*****************************************************************************
+# ****************************************************************************
 #       Copyright (C) 2007 William Stein <wstein@gmail.com>
 #
 # 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 cysignals.memory cimport check_allocarray, sig_free
 from cysignals.signals cimport sig_on, sig_off
 
-from sage.structure.element cimport Element, ModuleElement, RingElement, Vector
+from sage.structure.element cimport Element, Vector
 from sage.structure.richcmp cimport rich_to_bool
 from sage.rings.integer cimport Integer
 from sage.rings.rational cimport Rational
 
 cimport sage.modules.free_module_element as free_module_element
-from .free_module_element import vector
 
 from sage.libs.gmp.mpq cimport *
 
@@ -146,7 +145,7 @@ cdef class Vector_rational_dense(free_module_element.FreeModuleElement):
         cdef Rational z
         if isinstance(x, (list, tuple)):
             if len(x) != self._degree:
-                raise TypeError("entries must be a list of length %s"%self._degree)
+                raise TypeError("entries must be a list of length %s" % self._degree)
             for i from 0 <= i < self._degree:
                 z = Rational(x[i])
                 mpq_set(self._entries[i], z.value)
@@ -229,8 +228,7 @@ cdef class Vector_rational_dense(free_module_element.FreeModuleElement):
         """
         mpq_set(self._entries[i], (<Rational>value).value)
 
-
-    def list(self,copy=True):
+    def list(self, copy=True):
         """
         The list of entries of the vector.
 
@@ -248,8 +246,8 @@ cdef class Vector_rational_dense(free_module_element.FreeModuleElement):
             (1, 2, 3, 4)
         """
         cdef int i
-        return [_Rational_from_mpq(self._entries[i]) for i in
-                                  xrange(self._degree)]
+        return [_Rational_from_mpq(self._entries[i])
+                for i in range(self._degree)]
 
     def __reduce__(self):
         return (unpickle_v1, (self._parent, self.list(), self._degree,
@@ -264,7 +262,6 @@ cdef class Vector_rational_dense(free_module_element.FreeModuleElement):
             mpq_add(z._entries[i], self._entries[i], r._entries[i])
         return z
 
-
     cpdef _sub_(self, right):
         cdef Vector_rational_dense z, r
         r = right
@@ -299,7 +296,6 @@ cdef class Vector_rational_dense(free_module_element.FreeModuleElement):
         mpq_clear(t)
         return z
 
-
     cpdef _pairwise_product_(self, Vector right):
         """
         EXAMPLES::
@@ -326,7 +322,8 @@ cdef class Vector_rational_dense(free_module_element.FreeModuleElement):
             mpq_set_z(a.value, (<Integer>left).value)
         else:
             # should not happen
-            raise TypeError("cannot convert %s to %s" % (type(left).__name__, Rational.__name__))
+            raise TypeError("cannot convert %s to %s" % (type(left).__name__,
+                                                         Rational.__name__))
         z = self._new_c()
         cdef Py_ssize_t i
         for i in range(self._degree):
@@ -343,7 +340,8 @@ cdef class Vector_rational_dense(free_module_element.FreeModuleElement):
             mpq_set_z(a.value, (<Integer>right).value)
         else:
             # should not happen
-            raise TypeError("cannot convert %s to %s" % (type(right).__name__, Rational.__name__))
+            raise TypeError("cannot convert %s to %s" % (type(right).__name__,
+                                                         Rational.__name__))
         z = self._new_c()
         cdef Py_ssize_t i
         for i in range(self._degree):
@@ -374,6 +372,7 @@ def unpickle_v0(parent, entries, degree):
         mpq_set(v._entries[i], z.value)
     return v
 
+
 def unpickle_v1(parent, entries, degree, is_mutable):
     cdef Vector_rational_dense v
     v = Vector_rational_dense.__new__(Vector_rational_dense)

src/sage/modules/with_basis/indexed_element.pyx

@@ -23,14 +23,9 @@ from sage.structure.richcmp cimport richcmp, rich_to_bool
 from cpython.object cimport Py_NE, Py_EQ
 
 from sage.misc.repr import repr_lincomb
-from sage.misc.cachefunc import cached_method
-from sage.misc.lazy_attribute import lazy_attribute
 from sage.misc.superseded import deprecation
 from sage.typeset.ascii_art import AsciiArt, empty_ascii_art, ascii_art
 from sage.typeset.unicode_art import UnicodeArt, empty_unicode_art, unicode_art
-from sage.categories.category import Category
-from sage.categories.sets_cat import Sets
-from sage.categories.modules_with_basis import ModulesWithBasis
 from sage.data_structures.blas_dict cimport add, negate, scal, axpy