Clean python2 specifics

ppl/__init__.py

@@ -126,7 +126,6 @@
   Split the main code into several files.
   Remove the _mutable_immutable class.
 """
-from __future__ import absolute_import
 
 from .linear_algebra import (
         Variable, Variables_Set, Linear_Expression,

ppl/bit_arrays.pyx

@@ -9,8 +9,6 @@
 #                  http://www.gnu.org/licenses/
 #*****************************************************************************
 
-from __future__ import absolute_import, print_function
-
 from libc.limits cimport ULONG_MAX
 
 from .ppl_decl cimport PPL_Bit_Row

ppl/congruence.pyx

@@ -8,7 +8,6 @@
 #  the License, or (at youroption) any later version.
 #                  http://www.gnu.org/licenses/
 #*****************************************************************************
-from __future__ import absolute_import, print_function
 
 from cython.operator cimport dereference as deref
 

ppl/constraint.pyx

@@ -19,7 +19,6 @@
 #  the License, or (at youroption) any later version.
 #                  http://www.gnu.org/licenses/
 #*****************************************************************************
-from __future__ import absolute_import, print_function
 
 from gmpy2 cimport GMPy_MPZ_From_mpz, import_gmpy2
 from cython.operator cimport dereference as deref

ppl/generator.pyx

@@ -19,14 +19,11 @@
 #  the License, or (at youroption) any later version.
 #                  http://www.gnu.org/licenses/
 #*****************************************************************************
-from __future__ import absolute_import, print_function
 
 from gmpy2 cimport GMPy_MPZ_From_mpz, import_gmpy2
 from cython.operator cimport dereference as deref
 from .linear_algebra cimport PPL_Coefficient_from_pyobject
 
-import sys
-cdef int PY_MAJOR_VERSION = sys.version_info.major
 
 # PPL can use floating-point arithmetic to compute integers
 cdef extern from "ppl.hh" namespace "Parma_Polyhedra_Library":
@@ -667,24 +664,14 @@ cdef class Generator(object):
         """
         le = Linear_Expression(self.coefficients(), 0)
         t = self.thisptr.type()
-        if PY_MAJOR_VERSION == 2:
-            if t == LINE or t == RAY:
-                return (_unpickle_generator, (self.type(), le))
-            elif t == POINT or t == CLOSURE_POINT:
-                return (_unpickle_generator, (self.type(), le, self.divisor()))
-            else:
-                raise RuntimeError
-        elif PY_MAJOR_VERSION == 3:
-            if t == LINE:
-                return (Generator.line, (le,))
-            elif t == RAY:
-                return (Generator.ray, (le,))
-            elif t == POINT:
-                return (Generator.point, (le, self.divisor()))
-            elif t == CLOSURE_POINT:
-                return (Generator.closure_point, (le, self.divisor()))
-            else:
-                raise RuntimeError
+        if t == LINE:
+            return (Generator.line, (le,))
+        elif t == RAY:
+            return (Generator.ray, (le,))
+        elif t == POINT:
+            return (Generator.point, (le, self.divisor()))
+        elif t == CLOSURE_POINT:
+            return (Generator.closure_point, (le, self.divisor()))
         else:
             raise RuntimeError
 
@@ -1224,18 +1211,3 @@ cdef _wrap_Poly_Gen_Relation(PPL_Poly_Gen_Relation relation):
     cdef Poly_Gen_Relation rel = Poly_Gen_Relation(True)
     rel.thisptr = new PPL_Poly_Gen_Relation(relation)
     return rel
-
-if PY_MAJOR_VERSION == 2:
-    def _unpickle_generator(*args):
-        t = args[0]
-        args = args[1:]
-        if t == 'line':
-            return Generator.line(*args)
-        elif t == 'ray':
-            return Generator.ray(*args)
-        elif t == 'point':
-            return Generator.point(*args)
-        elif t == 'closure_point':
-            return Generator.closure_point(*args)
-        else:
-            raise RuntimeError

ppl/linear_algebra.pyx

@@ -20,8 +20,6 @@
 #                  http://www.gnu.org/licenses/
 #*****************************************************************************
 
-from __future__ import absolute_import, print_function
-
 cimport cython
 
 from gmpy2 cimport import_gmpy2, mpz, GMPy_MPZ_From_mpz, MPZ_Check

ppl/mip_problem.pyx

@@ -19,7 +19,6 @@
 #  the License, or (at youroption) any later version.
 #                  http://www.gnu.org/licenses/
 #*****************************************************************************
-from __future__ import absolute_import, print_function
 
 from cysignals.signals cimport sig_on, sig_off
 from gmpy2 cimport import_gmpy2, GMPy_MPQ_From_mpz

ppl/polyhedron.pyx

@@ -19,7 +19,6 @@
 #  the License, or (at youroption) any later version.
 #                  http://www.gnu.org/licenses/
 #*****************************************************************************
-from __future__ import absolute_import, print_function
 
 from cpython.object cimport Py_LT, Py_LE, Py_EQ, Py_NE, Py_GT, Py_GE
 from cysignals.signals cimport sig_on, sig_off