sagemathgh-38443: fix E302 in pxi files

    
just for the sake of house cleaning


### 📝 Checklist

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URL: sagemath#38443
Reported by: Frédéric Chapoton
Reviewer(s): Martin Rubey

src/sage/data_structures/list_of_pairs.pxd

@@ -4,6 +4,7 @@ cdef struct pair_s:
     size_t first
     size_t second
 
+
 @cython.final
 cdef class ListOfPairs:
     cdef pair_s** _lists

src/sage/libs/linkages/padics/unram_shared.pxi

@@ -1,5 +1,6 @@
 cimport cython
 
+
 @cython.binding(True)
 def frobenius_unram(self, arithmetic=True):
     """

src/sage/libs/symmetrica/kostka.pxi

@@ -6,6 +6,7 @@ cdef extern from 'symmetrica/def.h':
     INT kostka_tab(OP shape, OP content, OP result)
     INT kostka_tafel(OP n, OP result)
 
+
 def kostka_number_symmetrica(shape, content):
     """
     Compute the kostkanumber, i.e. the number of
@@ -53,6 +54,7 @@ def kostka_number_symmetrica(shape, content):
 
     return res
 
+
 def kostka_tab_symmetrica(shape, content):
     """
     Compute the list of tableaux of given shape
@@ -111,6 +113,7 @@ def kostka_tab_symmetrica(shape, content):
 
     return res
 
+
 def kostka_tafel_symmetrica(n):
     """
     Return the table of Kostka numbers of weight `n`.

src/sage/libs/symmetrica/part.pxi

@@ -6,6 +6,7 @@ cdef extern from 'symmetrica/def.h':
     INT gupta_tafel(OP max, OP res)
     INT random_partition(OP nx, OP res)
 
+
 def strict_to_odd_part_symmetrica(part):
     """
     Implement the bijection between strict partitions
@@ -36,6 +37,7 @@ def strict_to_odd_part_symmetrica(part):
 
     return res
 
+
 def odd_to_strict_part_symmetrica(part):
     """
     Implement the bijection between partitions with odd parts
@@ -129,6 +131,7 @@ def gupta_nm_symmetrica(n, m):
 
     return res
 
+
 def gupta_tafel_symmetrica(max):
     """
     It computes the table of the above values. The entry

src/sage/libs/symmetrica/plet.pxi

@@ -2,6 +2,7 @@ cdef extern from 'symmetrica/def.h':
     INT plethysm(OP s1, OP s2, OP res)
     INT schur_schur_plet(OP p1, OP p2, OP res)
 
+
 def plethysm_symmetrica(outer, inner):
     cdef OP couter = callocobject(), cinner = callocobject(), cresult = callocobject()
 

src/sage/libs/symmetrica/sab.pxi

@@ -91,6 +91,7 @@ def sdg_symmetrica(part, perm):
 
     return res
 
+
 def odg_symmetrica(part, perm):
     """
     Calculate the irreducible matrix representation
@@ -140,6 +141,7 @@ def ndg_symmetrica(part, perm):
 
     return res
 
+
 def specht_dg_symmetrica(part, perm):
     cdef OP cpart, cperm, cD
 

src/sage/libs/symmetrica/sb.pxi

@@ -64,6 +64,7 @@ def mult_schubert_schubert_symmetrica(a, b):
 
     return res
 
+
 def t_SCHUBERT_POLYNOM_symmetrica(a):
     """
     Convert a Schubert polynomial to a 'regular' multivariate
@@ -96,6 +97,7 @@ def t_SCHUBERT_POLYNOM_symmetrica(a):
 
     return res
 
+
 def t_POLYNOM_SCHUBERT_symmetrica(a):
     """
     Convert a multivariate polynomial a to a Schubert polynomial.
@@ -135,6 +137,7 @@ def t_POLYNOM_SCHUBERT_symmetrica(a):
 
     return res
 
+
 def mult_schubert_variable_symmetrica(a, i):
     """
     Return the product of `a` and `x_i`.  Note that indexing with `i`
@@ -270,6 +273,7 @@ def scalarproduct_schubert_symmetrica(a, b):
 
     return res
 
+
 def divdiff_schubert_symmetrica(i, a):
     r"""
     Return the result of applying the divided difference operator

src/sage/libs/symmetrica/schur.pxi

@@ -404,6 +404,7 @@ def compute_schur_with_alphabet_det_symmetrica(part, length, alphabet='x'):
 
     return res
 
+
 def part_part_skewschur_symmetrica(outer, inner):
     """
     Return the skew Schur function s_{outer/inner}.
@@ -430,6 +431,7 @@ def part_part_skewschur_symmetrica(outer, inner):
 
     return res
 
+
 def hall_littlewood_symmetrica(part):
     """
     Compute the so called Hall Littlewood Polynomials, i.e.
@@ -526,6 +528,7 @@ def t_SCHUR_POWSYM_symmetrica(schur):
 
     return res
 
+
 def t_POLYNOM_SCHUR_symmetrica(p):
     r"""
     Convert a symmetric polynomial with base ring `\QQ` or `\ZZ` into a
@@ -566,6 +569,7 @@ def t_MONOMIAL_HOMSYM_symmetrica(monomial):
 
     return res
 
+
 def t_MONOMIAL_ELMSYM_symmetrica(monomial):
     cdef OP cmonomial = callocobject(), cresult = callocobject()
 
@@ -616,6 +620,7 @@ def t_MONOMIAL_POWSYM_symmetrica(monomial):
 
     return res
 
+
 def t_POLYNOM_MONOMIAL_symmetrica(p):
     r"""
     Convert a symmetric polynomial with base ring `\QQ` or `\ZZ` into a
@@ -673,6 +678,7 @@ def t_ELMSYM_POWSYM_symmetrica(elmsym):
 
     return res
 
+
 def t_ELMSYM_MONOMIAL_symmetrica(elmsym):
     cdef OP celmsym = callocobject(), cresult = callocobject()
 
@@ -706,6 +712,7 @@ def t_ELMSYM_HOMSYM_symmetrica(elmsym):
 
     return res
 
+
 def t_POLYNOM_ELMSYM_symmetrica(p):
     r"""
     Convert a symmetric polynomial with base ring `\QQ` or `\ZZ` into a
@@ -746,6 +753,7 @@ def t_HOMSYM_SCHUR_symmetrica(homsym):
 
     return res
 
+
 def t_HOMSYM_POWSYM_symmetrica(homsym):
     cdef OP chomsym = callocobject(), cresult = callocobject()
 
@@ -779,6 +787,7 @@ def t_HOMSYM_MONOMIAL_symmetrica(homsym):
 
     return res
 
+
 def t_HOMSYM_ELMSYM_symmetrica(homsym):
     cdef OP chomsym = callocobject(), cresult = callocobject()
 
@@ -829,6 +838,7 @@ def t_POWSYM_SCHUR_symmetrica(powsym):
 
     return res
 
+
 def t_POWSYM_ELMSYM_symmetrica(powsym):
     cdef OP cpowsym = callocobject(), cresult = callocobject()
 
@@ -845,6 +855,7 @@ def t_POWSYM_ELMSYM_symmetrica(powsym):
 
     return res
 
+
 def t_POWSYM_HOMSYM_symmetrica(powsym):
     cdef OP cpowsym = callocobject(), cresult = callocobject()
 
@@ -861,6 +872,7 @@ def t_POWSYM_HOMSYM_symmetrica(powsym):
 
     return res
 
+
 def t_POLYNOM_POWER_symmetrica(p):
     r"""
     Convert a symmetric polynomial with base ring `\QQ` or `\ZZ` into a

src/sage/libs/symmetrica/symmetrica.pxi

@@ -522,6 +522,7 @@ cdef int _op(object a, OP result) except -1:
     else:
         raise TypeError("cannot convert a (= %s) to OP" % a)
 
+
 def test_integer(object x):
     """
     Test functionality for converting between Sage's integers

src/sage/rings/polynomial/polynomial_template.pxi

@@ -24,9 +24,11 @@ from sage.libs.pari.all import pari_gen
 
 import operator
 
+
 def make_element(parent, args):
     return parent(*args)
 
+
 cdef inline Polynomial_template element_shift(self, int n):
      if not isinstance(self, Polynomial_template):
          if n > 0:

src/sage/symbolic/getitem_impl.pxi

@@ -188,6 +188,7 @@ cdef class OperandsWrapper(SageObject):
         """
         return restore_op_wrapper, (self._expr,)
 
+
 def restore_op_wrapper(expr):
     """
     TESTS::

src/sage/symbolic/pynac_impl.pxi

@@ -1279,6 +1279,7 @@ cdef py_numer(n):
         except AttributeError:
             return n
 
+
 def py_numer_for_doctests(n):
     """
     This function is used to test py_numer().
@@ -1390,6 +1391,7 @@ cdef py_float(n, PyObject* kwds):
         except TypeError:
             return CC(n)
 
+
 def py_float_for_doctests(n, kwds):
     """
     This function is for testing py_float.
@@ -1450,6 +1452,7 @@ cdef py_tgamma(x):
             return CC(res)
     return res
 
+
 def py_tgamma_for_doctests(x):
     """
     This function is for testing py_tgamma().
@@ -1489,6 +1492,7 @@ cdef py_factorial(x):
     else:
         return py_tgamma(x+1)
 
+
 def py_factorial_py(x):
     """
     This function is a python wrapper around py_factorial(). This wrapper
@@ -1510,6 +1514,7 @@ cdef py_doublefactorial(x):
     from sage.misc.misc_c import prod  # fast balanced product
     return prod([n - 2*i for i in range(n//2)])
 
+
 def doublefactorial(n):
     """
     The double factorial combinatorial function:
@@ -1630,6 +1635,7 @@ cdef py_stieltjes(x):
         prec = 53
     return mpmath_utils.call(mpmath.stieltjes, n, prec=prec)
 
+
 def py_stieltjes_for_doctests(x):
     """
     This function is for testing py_stieltjes().
@@ -1664,6 +1670,7 @@ cdef py_zeta(x):
     except AttributeError:
         return CC(x).zeta()
 
+
 def py_zeta_for_doctests(x):
     """
     This function is for testing py_zeta().
@@ -1705,6 +1712,7 @@ cdef py_exp(x):
     except (TypeError, ValueError):
         return CC(x).exp()
 
+
 def py_exp_for_doctests(x):
     """
     This function tests py_exp.
@@ -1774,6 +1782,7 @@ cdef py_log(x):
     except (TypeError, ValueError):
         return CC(x).log()
 
+
 def py_log_for_doctests(x):
     """
     This function tests py_log.
@@ -2195,6 +2204,7 @@ cdef py_psi2(n, x):
         prec = 53
     return mpmath_utils.call(mpmath.psi, n, x, prec=prec)
 
+
 def py_psi2_for_doctests(n, x):
     """
     This function is a python wrapper so py_psi2 can be tested. The real tests
@@ -2268,6 +2278,7 @@ cdef py_eval_unsigned_infinity():
     from sage.rings.infinity import unsigned_infinity
     return unsigned_infinity
 
+
 def py_eval_unsigned_infinity_for_doctests():
     """
     This function tests py_eval_unsigned_infinity.
@@ -2287,6 +2298,7 @@ cdef py_eval_infinity():
     from sage.rings.infinity import infinity
     return infinity
 
+
 def py_eval_infinity_for_doctests():
     """
     This function tests py_eval_infinity.
@@ -2306,6 +2318,7 @@ cdef py_eval_neg_infinity():
     from sage.rings.infinity import minus_infinity
     return minus_infinity
 
+
 def py_eval_neg_infinity_for_doctests():
     """
     This function tests py_eval_neg_infinity.