Make script compatible Python 2 and Python 3

setuptools does not run 2to3 on the scripts so we must ensure the code is
compatible with both versions.

issue7057
review40951003

scripts/trytond_import_zip

@@ -1,14 +1,18 @@
 #!/usr/bin/env python
 # This file is part of Tryton.  The COPYRIGHT file at the top level of
 # this repository contains the full copyright notices and license terms.
+from __future__ import print_function
 import csv
 import os
 import sys
-import urllib2
+try:
+    from urllib.request import urlopen
+except ImportError:
+    from urllib2 import urlopen
 import zipfile
 
 from argparse import ArgumentParser
-from io import BytesIO
+from io import BytesIO, StringIO
 
 try:
     from progressbar import ProgressBar, Bar, ETA, SimpleProgress
@@ -27,17 +31,17 @@ def clean(code):
     Zip = Model.get('country.zip')
     Zip._proxy.delete(
         [z.id for z in Zip.find([('country.code', '=', code)])], {})
-    print >> sys.stderr, '.'
+    print('.', file=sys.stderr)
 
 
 def fetch(code):
     sys.stderr.write('Fetching')
     url = 'http://download.geonames.org/export/zip/%s.zip' % code
-    responce = urllib2.urlopen(url)
+    responce = urlopen(url)
     data = responce.read()
     with zipfile.ZipFile(BytesIO(data)) as zf:
         data = zf.read('%s.txt' % code)
-    print >> sys.stderr, '.'
+    print('.', file=sys.stderr)
     return data
 
 
@@ -45,7 +49,7 @@ def import_(data):
     Zip = Model.get('country.zip')
     Country = Model.get('country.country')
     Subdivision = Model.get('country.subdivision')
-    print >> sys.stderr, 'Importing'
+    print('Importing', file=sys.stderr)
 
     def get_country(code):
         country = countries.get(code)
@@ -72,8 +76,12 @@ def import_(data):
             widgets=[SimpleProgress(), Bar(), ETA()])
     else:
         pbar = iter
-    for row in pbar(list(csv.DictReader(BytesIO(data),
-                    fieldnames=_fieldnames, delimiter='\t'))):
+    if sys.version_info < (3,):
+        f = BytesIO(data)
+    else:
+        f = StringIO(data.decode('utf-8'))
+    for row in pbar(list(csv.DictReader(
+                    f, fieldnames=_fieldnames, delimiter='\t'))):
         country = get_country(row['country'])
         subdivision = get_subdivision(row['country'], row['code1'])
         Zip(country=country, subdivision=subdivision, zip=row['postal'],
@@ -87,7 +95,7 @@ def main(database, codes, config_file=None):
     config.set_trytond(database, config_file=config_file)
 
     for code in codes:
-        print >> sys.stderr, code
+        print(code, file=sys.stderr)
         code = code.upper()
         clean(code)
         import_(fetch(code))