pyupgrade: Reformat with --py36-plus.

This includes mainly fixes of string literals using f-strings or
.format(...), as well as unpacking of list comprehensions.

zulip_botserver/setup.py

@@ -72,11 +72,11 @@ except ImportError:
         except (ImportError, AssertionError):
             if version is not None:
                 print(
-                    "{name}>={version} is not installed.".format(name=module_name, version=version),
+                    f"{module_name}>={version} is not installed.",
                     file=sys.stderr,
                 )
             else:
-                print("{name} is not installed.".format(name=module_name), file=sys.stderr)
+                print(f"{module_name} is not installed.", file=sys.stderr)
             sys.exit(1)
 
     check_dependency_manually("zulip")

zulip_botserver/tests/server_test_lib.py

@@ -1,9 +1,7 @@
 import configparser
 import json
 from typing import Any, Dict, List, Optional
-from unittest import TestCase
-
-import mock
+from unittest import TestCase, mock
 
 from zulip_botserver import server
 

zulip_botserver/tests/test_server.py

@@ -6,8 +6,7 @@ from importlib import import_module
 from pathlib import Path
 from types import ModuleType
 from typing import Any, Dict
-
-import mock
+from unittest import mock
 
 from zulip_bots.lib import BotHandler
 from zulip_botserver import server

zulip_botserver/zulip_botserver/server.py

@@ -98,7 +98,7 @@ def read_config_file(
         ignored_sections = parser.sections()[1:]
 
     if len(ignored_sections) > 0:
-        logging.warning("Sections except the '{}' will be ignored".format(bot_section))
+        logging.warning(f"Sections except the '{bot_section}' will be ignored")
 
     return bots_config
 
@@ -106,7 +106,7 @@ def read_config_file(
 def parse_config_file(config_file_path: str) -> configparser.ConfigParser:
     config_file_path = os.path.abspath(os.path.expanduser(config_file_path))
     if not os.path.isfile(config_file_path):
-        raise OSError("Could not read config file {}: File not found.".format(config_file_path))
+        raise OSError(f"Could not read config file {config_file_path}: File not found.")
     parser = configparser.ConfigParser()
     parser.read(config_file_path)
     return parser