a few fixes for pycodestyle

Author: fchapoton

src/sage/graphs/connectivity.pyx

@@ -777,6 +777,7 @@ def blocks_and_cuts_tree(G):
                 g.add_edge(('B', bloc), ('C', c))
     return g
 
+
 def biconnected_components_subgraphs(G):
     r"""
     Return a list of biconnected components as graph objects.
@@ -816,6 +817,7 @@ def biconnected_components_subgraphs(G):
 
     return [G.subgraph(c) for c in blocks_and_cut_vertices(G)[0]]
 
+
 def is_edge_cut(G, edges):
     """
     Check whether ``edges`` form an edge cut.

src/sage/interfaces/khoca.py

@@ -183,7 +183,7 @@ def prepare_data(data):
             # i[0]: degree, i[1]: height, i[2]: torsion i[3]: rank
             d, h, t, r = i
             # make d compatibil with Sage
-            d = int(t/2) - d
+            d = int(t / 2) - d
             if (h, d, t) in data_as_dict:
                 data_as_dict[(h, d, t)] += r
             else:
@@ -207,7 +207,7 @@ def prepare_data(data):
     raw_data = khoca_raw_data(link, ring, red_typ=False, **kwds)
     if 'reduced' in kwds:
         red = kwds['reduced']
-        if type(red) == bool:
+        if isinstance(red, bool):
             if red:
                 return raw_data['red']
             else:

src/sage/interfaces/regina.py

@@ -338,7 +338,7 @@ def set(self, var, value):
         """
         self._lazy_init()
         globs = self._regina_globals
-        if type(value) != str:
+        if not isinstance(value, str):
             globs[var] = value
             return
         try:
@@ -428,7 +428,7 @@ def _convert_args_kwds(self, *args, **kwds):
         def convert_arg(arg):
             if isinstance(arg, InterfaceElement) and arg.parent() is self:
                 return arg._inst
-            elif type(arg) in (list, tuple):
+            elif isinstance(arg, (list, tuple)):
                 return type(arg)([convert_arg(i) for i in arg])
             elif hasattr(arg, '_regina_'):
                 reg = arg._regina_(self)
@@ -832,9 +832,9 @@ def is_native(inst):
         if operation in ('+', '*'):
             if is_native(sinst) and is_native(oinst):
                 if operation == '*':
-                    return P(sinst*oinst)
+                    return P(sinst * oinst)
                 else:
-                    return P(sinst+oinst)
+                    return P(sinst + oinst)
             if type(sinst) == type(oinst):
                 if hasattr(self, 'addTermsLast'):
                     new = self.__deepcopy__()
@@ -860,7 +860,7 @@ def is_native(inst):
                 return (~self)**(-exp)
         if operation == '1/':
             if is_native(sinst):
-                return P(1/sinst)
+                return P(1 / sinst)
             if hasattr(self, 'inverse'):
                 return self.inverse()
         return super()._operation(operation, other=other)
@@ -919,7 +919,6 @@ def from_detail_str(lc):
             """
             if locals:
                 lc.update(locals)
-            from sage.repl.preparse import implicit_mul
             from sage.misc.sage_eval import sage_eval
             s = self.detail().split('\n')[0]
             s = s.replace(' ', '')

src/sage/libs/gap/element.pyx

@@ -1006,7 +1006,6 @@ cdef class GapElement(RingElement):
             GAP_Leave()
             gap_sig_off()
 
-
     cdef bint _compare_less(self, Element other) except -2:
         """
         Compare ``self`` with ``other``.
@@ -1030,7 +1029,6 @@ cdef class GapElement(RingElement):
             GAP_Leave()
             gap_sig_off()
 
-
     cpdef _add_(self, right):
         r"""
         Add two GapElement objects.

src/sage/matrix/matrix2.pyx

@@ -19588,7 +19588,7 @@ cdef class Matrix(Matrix1):
             k = row_profile_exhausted + row_profile_self + row_extension
 
             # calculate sorting permutation, sort k by (shifts[c]+d, c)
-            k_rows = [x[2] for x in  self._krylov_row_coordinates(shifts, degrees, k)]
+            k_rows = [x[2] for x in self._krylov_row_coordinates(shifts, degrees, k)]
             k_perm = Permutation([x + 1 for x in k_rows])
 
             # fast calculation of rows formed by indices in k
@@ -19633,7 +19633,7 @@ cdef class Matrix(Matrix1):
             k = row_profile_exhausted + row_profile_self
             R = exhausted.stack(R)
 
-            k_rows = [x[2] for x in  self._krylov_row_coordinates(shifts, degrees, k)]
+            k_rows = [x[2] for x in self._krylov_row_coordinates(shifts, degrees, k)]
             k_perm = Permutation([x + 1 for x in k_rows])
 
             R.permute_rows(k_perm)

src/sage/rings/finite_rings/integer_mod_ring.py

@@ -1986,7 +1986,7 @@ def _roots_univariate_polynomial(self, f, ring=None, multiplicities=True, algori
                 g = N.gcd(al)
 
                 if bl % g != 0:
-                    return [] # No solution
+                    return []  # No solution
                 else:
                     # whole eqn divided by g
                     N_by_g = N.divide_knowing_divisible_by(g)
@@ -1997,8 +1997,7 @@ def _roots_univariate_polynomial(self, f, ring=None, multiplicities=True, algori
                     # single root
                     _root = self(f.roots(_R, multiplicities=False)[0])
                     inc = self(N_by_g)
-                    return [_root + k*inc for k in range(g)]
-
+                    return [_root + k * inc for k in range(g)]
 
         # Finite fields are a base case
         if self.is_field():

src/sage/structure/element.pyx

@@ -3215,7 +3215,7 @@ cdef class CommutativeRingElement(RingElement):
         return I.reduce(self)
 
 
-    ##############################################
+##############################################
 
 cdef class Expression(CommutativeRingElement):