Fix Python code: remove imports from `python-future`.

I missed in 3d6ba937a5a5046b3d531c17691d5d1155daae71 that `future`
also provides the modules `past` and `builtins`.
Imports of `builtins` can simply be removed for Python-3-only code.
`past.old_div` had to be replaces by the "old" div-operatot `//`,
while `past.xrange` was unused.

4 files changed, 2 insertions, 10 deletions

diff --git a/src/consensus/consensus-simulation.py.in b/src/consensus/consensus-simulation.py.in
index 23639b195..39daf81c6 100644
--- a/src/consensus/consensus-simulation.py.in
+++ b/src/consensus/consensus-simulation.py.in
@@ -17,13 +17,9 @@
 #
 # SPDX-License-Identifier: AGPL3.0-or-later
 
-from builtins import str
-from builtins import range
-from past.utils import old_div
 import argparse
 import random
 from math import ceil, log, floor
-from past.builtins import xrange
 
 
 def bsc(n):
@@ -40,7 +36,7 @@ def bsc(n):
 
 def simulate(k, n, verbose):
     assert k < n
-    largest_arc = old_div(int(2**ceil(log(n, 2))), 2)
+    largest_arc = int(2**ceil(log(n, 2))) // 2
     num_ghosts = (2 * largest_arc) - n
     if verbose:
         print("we have", num_ghosts, "ghost peers")
@@ -106,4 +102,4 @@ if __name__ == "__main__":
     sum = 0.0
     for n in range(0, args.r):
         sum += simulate(args.k, args.n, args.verbose)
-    print(old_div(sum, args.r))
+    print(sum // args.r)
diff --git a/src/integration-tests/gnunet_pyexpect.py.in b/src/integration-tests/gnunet_pyexpect.py.in
index 000b8f99a..d757634a5 100644
--- a/src/integration-tests/gnunet_pyexpect.py.in
+++ b/src/integration-tests/gnunet_pyexpect.py.in
@@ -19,7 +19,6 @@
 #
 # Testcase for gnunet-peerinfo
 
-from builtins import object
 import os
 import re
 import subprocess
diff --git a/src/integration-tests/gnunet_testing.py.in b/src/integration-tests/gnunet_testing.py.in
index 667c3fff5..c3596d232 100644
--- a/src/integration-tests/gnunet_testing.py.in
+++ b/src/integration-tests/gnunet_testing.py.in
@@ -19,8 +19,6 @@
 #
 # Functions for integration testing
 
-from builtins import object
-from builtins import str
 import os
 import subprocess
 import sys
diff --git a/src/revocation/test_local_revocation.py.in b/src/revocation/test_local_revocation.py.in
index 979a55d83..4cc6119ca 100644
--- a/src/revocation/test_local_revocation.py.in
+++ b/src/revocation/test_local_revocation.py.in
@@ -19,7 +19,6 @@
 #
 # Testcase for ego revocation
 
-from builtins import str
 import sys
 import os
 import subprocess