Restore compatibility with python 3.5

.pylintrc

@@ -4,3 +4,4 @@ disable=invalid-name,
 	too-many-arguments,
 	too-many-branches,
 	line-too-long,
+	consider-using-f-string,  # to keep compatibility with python 3.5

gitdch

@@ -15,7 +15,9 @@ DEFAULT_GIT_PATCH = './'
 DEFAULT_CODE_NAME = 'unstable'
 DEFAULT_URGENCY = 'medium'
 
-parser = argparse.ArgumentParser(description=f'{__doc__} (version: {VERSION})')
+parser = argparse.ArgumentParser(
+    description='{0} (version: {1})'.format(__doc__, VERSION)
+)
 
 parser.add_argument(
     '-d', '--debug',
@@ -55,7 +57,7 @@ parser.add_argument(
     '--path',
     type=str,
     dest='git_path',
-    help=f'Git repository path (default: {DEFAULT_GIT_PATCH}',
+    help='Git repository path (default: %s)' % DEFAULT_GIT_PATCH,
     default=DEFAULT_GIT_PATCH
 )
 
@@ -97,7 +99,7 @@ parser.add_argument(
     '--code-name',
     type=str,
     dest='code_name',
-    help=f'Debian code name (default: {DEFAULT_CODE_NAME})',
+    help='Debian code name (default: %s)' % DEFAULT_CODE_NAME,
     default=DEFAULT_CODE_NAME
 )
 
@@ -106,7 +108,7 @@ parser.add_argument(
     '--urgency',
     type=str,
     dest='urgency',
-    help=f'Package urgency (default: {DEFAULT_URGENCY})',
+    help='Package urgency (default: %s)' % DEFAULT_URGENCY,
     default=DEFAULT_URGENCY
 )
 
@@ -144,8 +146,9 @@ if not options.package_name:
 # Initialize log
 log = logging.getLogger()
 logformat = logging.Formatter(
-    f'%(asctime)s - {os.path.basename(sys.argv[0])} - %(levelname)s '
-    ': %(message)s'
+    '%(asctime)s - {} - %(levelname)s : %(message)s'.format(
+        os.path.basename(sys.argv[0])
+    )
 )
 # Set root logger to DEBUG (filtering done by handlers)
 log.setLevel(logging.DEBUG)
@@ -272,7 +275,7 @@ if options.release_notes:
     log.info('Generate Markdown release notes')
     release_notes_lines = ['# Changelog:\n\n']
     release_notes_lines.extend([
-        f'* {message}\n'
+        '* {0}\n'.format(message)
         for message in versions[0]['messages']
     ])
     log.info(