gh-35244: fix pep E303 in all folders starting with [defghi]

    
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### 📚 Description

This fixes all pycodestyle warning about E303 in all folders whose first
letter is among `defghi`.

```E303 too many blank lines```


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URL: #35244
Reported by: Frédéric Chapoton
Reviewer(s): Matthias Köppe

src/sage/data_structures/stream.py

@@ -2015,7 +2015,6 @@ def _approximate_order(self):
 #                             " support")
         return self._left._approximate_order * self._right._approximate_order
 
-
     def get_coefficient(self, n):
         r"""
         Return the ``n``-th coefficient of ``self``.
@@ -2765,7 +2764,6 @@ def order(self):
         """
         return self._series.order() + self._shift
 
-
     def __getitem__(self, n):
         """
         Return the ``n``-th coefficient of ``self``.

src/sage/databases/findstat.py

@@ -2919,7 +2919,6 @@ def browse(self):
         """
         webbrowser.open(FINDSTAT_URL_STATISTICS + self.id_str())
 
-
     def info(self):
         """
         Print a detailed description of the compound statistic.

src/sage/databases/knotinfo_db.py

@@ -262,7 +262,6 @@ def sobj_column(self):
         """
         return 'column_dict.sobj'
 
-
     def sobj_data(self, column):
         r"""
         Return the file name under which the data of the given
@@ -311,13 +310,10 @@ def diagram_url(self, fname, single=False):
         else:
             return '%sdiagram_display.php?%s' %(self.url(), fname)
 
-
     knots = ['https://knotinfo.math.indiana.edu/', 'knotinfo_data_complete']
     links = ['https://linkinfo.sitehost.iu.edu/',  'linkinfo_data_complete']
 
 
-
-
 #----------------------------------------------------------------------------------------------------------------------------
 # Class to provide data for knots and links from the KnotInfo web-page
 #----------------------------------------------------------------------------------------------------------------------------
@@ -406,7 +402,6 @@ def create_filecache(self, force=False):
             self._create_data_sobj(sobj_path=sobj_path)
         return
 
-
     def version(self):
         r"""
         Return the version of the database currently installed on the device.
@@ -439,7 +434,6 @@ def version(self):
         from database_knotinfo import version
         return version()
 
-
     def demo_version(self):
         r"""
         Return whether the KnotInfo databases are installed completely or
@@ -483,7 +477,6 @@ def knot_list(self):
         self._knot_list = link_list()
         return self._knot_list
 
-
     def link_list(self):
         r"""
         Return the LinkInfo table rows as Python list.
@@ -557,8 +550,6 @@ def _create_col_dict_sobj(self, sobj_path=None):
 
         save(column_dict, '%s/%s' %(sobj_path, self.filename.knots.sobj_column()))
 
-
-
     def _create_data_sobj(self, sobj_path=None):
         r"""
         Create ``sobj`` files containing the contents of the whole table.
@@ -621,7 +612,6 @@ def _create_data_sobj(self, sobj_path=None):
 
         save(row_dict,    '%s/%s' %(sobj_path, self.filename.knots.sobj_row()))
 
-
     @cached_method
     def columns(self):
         r"""
@@ -639,7 +629,6 @@ def columns(self):
         column_dict = self.read_column_dict()
         return KnotInfoColumns('Columns', column_dict)
 
-
     # -------------------------------------------------------------------------------------------------------------
     # read the dictionary for the column names from sobj-file
     # -------------------------------------------------------------------------------------------------------------
@@ -717,7 +706,6 @@ def row_names(self):
         names = self.read(self.columns().name)
         return {k:names[v[0]] for k, v in row_dict.items()}
 
-
     # -------------------------------------------------------------------------------------------------------------
     # read the number of knots contained in the database (without proper links) from the according sobj-file.
     # -------------------------------------------------------------------------------------------------------------
@@ -741,7 +729,6 @@ def read_num_knots(self):
             self.demo_version()
         return self._num_knots
 
-
     # -------------------------------------------------------------------------------------------------------------
     # read an sobj-file obtained from KnotInfo database
     # -------------------------------------------------------------------------------------------------------------
@@ -803,7 +790,6 @@ def _test_database(self, **options):
         tester.assertTrue(all(L.is_recoverable(unique=False) for L, in sample))
 
 
-
 column_demo_sample = {
     'name':                 ['Name',                 KnotInfoColumnTypes.KnotsAndLinks],
     'name_unoriented':      ['Name - Unoriented',    KnotInfoColumnTypes.OnlyLinks],

src/sage/doctest/reporting.py

@@ -556,7 +556,6 @@ def report(self, source, timeout, return_code, results, output, pid=None):
             import traceback
             log(traceback.format_exc(), end="")
 
-
     def finalize(self):
         """
         Print out the postscript that summarizes the doctests that were run.

src/sage/features/__init__.py

@@ -265,7 +265,6 @@ def resolution(self):
         return self._cache_resolution
 
 
-
 class FeatureNotPresentError(RuntimeError):
     r"""
     A missing feature error.

src/sage/finance/markov_multifractal.py

@@ -261,7 +261,6 @@ def simulations(self, n, k=1):
                    self.__kbar, self.gamma())
 
 
-
 ## def ml_estimation(v, kbar, M):
 ##     """
 ##     Compute parameters that model the time series v,

src/sage/functions/exp_integral.py

@@ -336,7 +336,6 @@ def _evalf_(self, z, parent=None, algorithm=None):
         import mpmath
         return mpmath_utils_call(mpmath.e1, z, parent=parent)
 
-
     def _print_latex_(self, z):
         r"""
         Custom ``_print_latex_`` method.

src/sage/games/hexad.py

@@ -107,7 +107,6 @@ def view_list(L):
     return matrix(GF(2), 3, 3, lambda x, y: 1 if (x,y) in L else 0)
 
 
-
 def picture_set(A, L):
     """
     This is needed in the :meth:`Minimog.find_hexad` function below.

src/sage/games/sudoku.py

@@ -410,7 +410,6 @@ def to_matrix(self):
         from sage.matrix.constructor import matrix
         return matrix(ZZ, self.n*self.n, self.puzzle)
 
-
     def to_ascii(self):
         r"""
         Construct an ASCII-art version of a Sudoku puzzle.

src/sage/geometry/cone.py

@@ -6779,7 +6779,6 @@ def is_valid(K):
             K = Cone(rays, lattice=L)
             rays = list(K.rays()) # Avoid re-normalizing next time around
 
-
         if strictly_convex is not None:
             if strictly_convex:
                 if not K.is_strictly_convex():

src/sage/geometry/fan_isomorphism.py

@@ -16,7 +16,6 @@
 from sage.geometry.cone import Cone
 
 
-
 class FanNotIsomorphicError(Exception):
     """
     Exception to return if there is no fan isomorphism

src/sage/geometry/hyperplane_arrangement/library.py

@@ -65,7 +65,6 @@ def make_parent(base_ring, dimension, names=None):
     return HyperplaneArrangements(base_ring, names=names)
 
 
-
 class HyperplaneArrangementLibrary():
     """
     The library of hyperplane arrangements.

src/sage/geometry/hyperplane_arrangement/plot.py

@@ -284,9 +284,6 @@ def plot(hyperplane_arrangement, **kwds):
             return p
 
 
-
-
-
 def plot_hyperplane(hyperplane, **kwds):
     r"""
     Return the plot of a single hyperplane.

src/sage/geometry/newton_polygon.py

@@ -523,8 +523,6 @@ def reverse(self, degree=None):
         return parent(polyhedron)
 
 
-
-
 class ParentNewtonPolygon(Parent, UniqueRepresentation):
     r"""
     Construct a Newton polygon.

src/sage/geometry/polyhedron/backend_polymake.py

@@ -688,7 +688,6 @@ def __setstate__(self, state):
             inequalities = self.inequalities()
             equations = self.equations()
 
-
         p = self._polymake_polytope_from_Vrepresentation_and_Hrepresentation([vertices, rays, lines], [inequalities, equations])
         if p is not None:
             self._polymake_polytope = p

src/sage/geometry/polyhedron/backend_ppl.py

@@ -539,7 +539,6 @@ def _convert_constraints_to_ppl(ieqs, eqns):
         return cs
 
 
-
 #########################################################################
 class Polyhedron_QQ_ppl(Polyhedron_ppl, Polyhedron_QQ):
     r"""

src/sage/geometry/polyhedron/base3.py

@@ -629,7 +629,6 @@ def face_generator(self, face_dimension=None, algorithm=None, **kwds):
             if 'dual' in kwds and dual is None:
                 dual = kwds['dual']
 
-
         from sage.geometry.polyhedron.combinatorial_polyhedron.face_iterator import FaceIterator_geom
         return FaceIterator_geom(self, output_dimension=face_dimension, dual=dual)
 

src/sage/geometry/polyhedron/base_RDF.py

@@ -6,7 +6,6 @@
 from .base import Polyhedron_base
 
 
-
 class Polyhedron_RDF(Polyhedron_base):
     """
     Base class for polyhedra over ``RDF``.

src/sage/geometry/polyhedron/ppl_lattice_polytope.py

@@ -179,7 +179,6 @@ def LatticePolytope_PPL(*args):
     return polytope_class(gs)
 
 
-
 ########################################################################
 class LatticePolytope_PPL_class(C_Polyhedron):
     """

src/sage/geometry/polyhedron/representation.py

@@ -1037,7 +1037,6 @@ def type(self):
         """
         return self.EQUATION
 
-
     def is_equation(self):
         """
         Tests if this object is an equation.  By construction, it must be.