diff --git a/bot/__init__.py b/bot/__init__.py
index 26693283..ec546d30 100644
--- a/bot/__init__.py
+++ b/bot/__init__.py
@@ -80,9 +80,7 @@
 else:
     AUTHORIZED_USERS = set()
 
-DATABASE_URL = os.environ.get('DATABASE_URL', '')
-if len(DATABASE_URL) == 0:
-    DATABASE_URL = None
+DATABASE_URL = os.environ.get('DATABASE_URL', None)
 
 IS_TEAM_DRIVE = os.environ.get('IS_TEAM_DRIVE', '')
 IS_TEAM_DRIVE = IS_TEAM_DRIVE.lower() == 'true'
@@ -90,12 +88,9 @@
 USE_SERVICE_ACCOUNTS = os.environ.get('USE_SERVICE_ACCOUNTS', '')
 USE_SERVICE_ACCOUNTS = USE_SERVICE_ACCOUNTS.lower() == 'true'
 
-DOWNLOAD_DIR = os.environ.get('DOWNLOAD_DIR', '')
-if len(DOWNLOAD_DIR) == 0:
-    DOWNLOAD_DIR = '/usr/src/app/downloads/'
-else:
-    if not DOWNLOAD_DIR.endswith('/'):
-        DOWNLOAD_DIR = DOWNLOAD_DIR + '/'
+DOWNLOAD_DIR = os.environ.get('DOWNLOAD_DIR', '/usr/src/app/downloads/')
+if not DOWNLOAD_DIR.endswith('/'):
+    DOWNLOAD_DIR = DOWNLOAD_DIR + '/'
 
 STATUS_UPDATE_INTERVAL = os.environ.get('STATUS_UPDATE_INTERVAL', '')
 STATUS_UPDATE_INTERVAL = 10 if len(STATUS_UPDATE_INTERVAL) == 0 else int(STATUS_UPDATE_INTERVAL)
@@ -103,9 +98,7 @@
 TELEGRAPH_ACCS = os.environ.get('TELEGRAPH_ACCS', '')
 TELEGRAPH_ACCS = 1 if len(TELEGRAPH_ACCS) == 0 else int(TELEGRAPH_ACCS)
 
-INDEX_URL = os.environ.get('INDEX_URL', '').rstrip("/")
-if len(INDEX_URL) == 0:
-    INDEX_URL = None
+INDEX_URL = os.environ.get('INDEX_URL', None).rstrip("/")
 
 ARCHIVE_LIMIT = os.environ.get('ARCHIVE_LIMIT', '')
 ARCHIVE_LIMIT = None if len(ARCHIVE_LIMIT) == 0 else float(ARCHIVE_LIMIT)
@@ -152,15 +145,10 @@
     except Exception as err:
         LOGGER.error(f"DRIVE_LIST_URL: {err}")
 
-APPDRIVE_EMAIL = os.environ.get('APPDRIVE_EMAIL', '')
-APPDRIVE_PASS = os.environ.get('APPDRIVE_PASS', '')
-if len(APPDRIVE_EMAIL) == 0 or len(APPDRIVE_PASS) == 0:
-    APPDRIVE_EMAIL = None
-    APPDRIVE_PASS = None
+APPDRIVE_EMAIL = os.environ.get('APPDRIVE_EMAIL', None)
+APPDRIVE_PASS = os.environ.get('APPDRIVE_PASS', None)
 
-GDTOT_CRYPT = os.environ.get('GDTOT_CRYPT', '')
-if len(GDTOT_CRYPT) == 0:
-    GDTOT_CRYPT = None
+GDTOT_CRYPT = os.environ.get('GDTOT_CRYPT', None)
 
 if os.path.exists('drive_list'):
     with open('drive_list', 'r+') as f:
diff --git a/bot/helper/drive_utils/gdriveTools.py b/bot/helper/drive_utils/gdriveTools.py
index bf92c92e..50ffb51e 100644
--- a/bot/helper/drive_utils/gdriveTools.py
+++ b/bot/helper/drive_utils/gdriveTools.py
@@ -16,7 +16,7 @@
 from google.oauth2 import service_account
 from google.oauth2.credentials import Credentials
 from googleapiclient.discovery import build
-from googleapiclient.errors import Error as GCError, HttpError
+from googleapiclient.errors import HttpError
 from googleapiclient.http import MediaFileUpload, MediaIoBaseDownload
 
 from bot import LOGGER, DRIVE_NAMES, DRIVE_IDS, INDEX_URLS, DRIVE_FOLDER_ID, \
@@ -138,16 +138,16 @@ def __getIdFromUrl(link: str):
 
     @retry(wait=wait_exponential(multiplier=2, min=3, max=6),
            stop=stop_after_attempt(3),
-           retry=retry_if_exception_type(GCError))
+           retry=retry_if_exception_type(Exception))
     def __getFileMetadata(self, file_id):
         return self.__service.files().get(
-                   supportsAllDrives=True,
                    fileId=file_id,
+                   supportsAllDrives=True,
                    fields='name, id, mimeType, size').execute()
 
     @retry(wait=wait_exponential(multiplier=2, min=3, max=6),
            stop=stop_after_attempt(3),
-           retry=retry_if_exception_type(GCError))
+           retry=retry_if_exception_type(Exception))
     def __getFilesByFolderId(self, folder_id):
         page_token = None
         query = f"'{folder_id}' in parents and trashed = false"
@@ -236,7 +236,7 @@ def deleteFile(self, link: str):
         try:
             self.__service.files().delete(
                 fileId=file_id,
-                supportsAllDrives=IS_TEAM_DRIVE).execute()
+                supportsAllDrives=True).execute()
             msg = "Permanently deleted"
         except HttpError as err:
             err = str(err).replace('>', '').replace('<', '')
@@ -259,9 +259,9 @@ def __set_permission_public(self, file_id):
             'role': 'reader'
         }
         return self.__service.permissions().create(
-                   supportsAllDrives=True,
                    fileId=file_id,
-                   body=permissions).execute()
+                   body=permissions,
+                   supportsAllDrives=True).execute()
 
     def __set_permission_email(self, file_id, email):
         permissions = {
@@ -270,9 +270,9 @@ def __set_permission_email(self, file_id, email):
             'emailAddress': email
         }
         return self.__service.permissions().create(
-                   supportsAllDrives=True,
                    fileId=file_id,
                    body=permissions,
+                   supportsAllDrives=True,
                    sendNotificationEmail=False).execute()
 
     def setPermission(self, link, access):
@@ -307,7 +307,7 @@ def setPermission(self, link, access):
 
     @retry(wait=wait_exponential(multiplier=2, min=3, max=6),
            stop=stop_after_attempt(3),
-           retry=retry_if_exception_type(GCError))
+           retry=retry_if_exception_type(Exception))
     def __create_directory(self, directory_name, dest_id):
         file_metadata = {
             "name": directory_name,
@@ -316,8 +316,8 @@ def __create_directory(self, directory_name, dest_id):
         if dest_id is not None:
             file_metadata["parents"] = [dest_id]
         file = self.__service.files().create(
-                   supportsAllDrives=True,
-                   body=file_metadata).execute()
+                   body=file_metadata,
+                   supportsAllDrives=True).execute()
         file_id = file.get("id")
         if not IS_TEAM_DRIVE:
             self.__set_permission_public(file_id)
@@ -325,16 +325,16 @@ def __create_directory(self, directory_name, dest_id):
 
     @retry(wait=wait_exponential(multiplier=2, min=3, max=6),
            stop=stop_after_attempt(3),
-           retry=retry_if_exception_type(GCError))
+           retry=retry_if_exception_type(Exception))
     def __copyFile(self, file_id, dest_id):
         body = {
             'parents': [dest_id]
         }
         try:
             res = self.__service.files().copy(
-                      supportsAllDrives=True,
                       fileId=file_id,
-                      body=body).execute()
+                      body=body,
+                      supportsAllDrives=True).execute()
             return res
         except HttpError as err:
             if err.resp.get('content-type', '').startswith('application/json'):
@@ -371,7 +371,7 @@ def __cloneFolder(self, name, local_path, folder_id, dest_id):
             if self.__is_cancelled:
                 break
 
-    def clone(self, link, dest_id):
+    def clone(self, link, __dest_id):
         self.__is_cloning = True
         self.__start_time = time.time()
         self.__total_files = 0
@@ -382,7 +382,8 @@ def clone(self, link, dest_id):
             msg = "Drive ID not found"
             LOGGER.error(msg)
             return msg
-        if dest_id != "":
+        if __dest_id != "":
+            dest_id = __dest_id
             index_url = None
         else:
             dest_id = DRIVE_FOLDER_ID
@@ -433,7 +434,7 @@ def clone(self, link, dest_id):
                 token_service = self.__alt_authorize()
                 if token_service is not None:
                     self.__service = token_service
-                    return self.clone(link, dest_id)
+                    return self.clone(link, __dest_id)
                 msg = "File not found"
             else:
                 msg = err
@@ -491,7 +492,7 @@ def _progress(self):
 
     @retry(wait=wait_exponential(multiplier=2, min=3, max=6),
            stop=stop_after_attempt(3),
-           retry=(retry_if_exception_type(GCError) | retry_if_exception_type(IOError)))
+           retry=(retry_if_exception_type(Exception)))
     def __upload_file(self, file_path, file_name, mime_type, dest_id):
         file_metadata = {
             'name': file_name,
@@ -502,26 +503,24 @@ def __upload_file(self, file_path, file_name, mime_type, dest_id):
         if os.path.getsize(file_path) == 0:
             media_body = MediaFileUpload(file_path, mimetype=mime_type, resumable=False)
             response = self.__service.files().create(
-                           supportsAllDrives=True,
                            body=file_metadata,
-                           media_body=media_body).execute()
+                           media_body=media_body,
+                           supportsAllDrives=True).execute()
             if not IS_TEAM_DRIVE:
                 self.__set_permission_public(response['id'])
             drive_file = self.__service.files().get(
-                             supportsAllDrives=True,
-                             fileId=response['id']).execute()
+                             fileId=response['id'],
+                             supportsAllDrives=True).execute()
             download_url = self.__G_DRIVE_BASE_DOWNLOAD_URL.format(drive_file.get('id'))
             return download_url
         media_body = MediaFileUpload(file_path, mimetype=mime_type, resumable=True,
                                      chunksize=50 * 1024 * 1024)
         drive_file = self.__service.files().create(
-                         supportsAllDrives=True,
                          body=file_metadata,
-                         media_body=media_body)
+                         media_body=media_body,
+                         supportsAllDrives=True)
         response = None
-        while response is None:
-            if self.__is_cancelled:
-                break
+        while response is None and not self.__is_cancelled:
             try:
                 self.__status, response = drive_file.next_chunk()
             except HttpError as err:
@@ -541,8 +540,8 @@ def __upload_file(self, file_path, file_name, mime_type, dest_id):
         if not IS_TEAM_DRIVE:
             self.__set_permission_public(response['id'])
         drive_file = self.__service.files().get(
-                         supportsAllDrives=True,
-                         fileId=response['id']).execute()
+                         fileId=response['id'],
+                         supportsAllDrives=True).execute()
         download_url = self.__G_DRIVE_BASE_DOWNLOAD_URL.format(drive_file.get('id'))
         return download_url
 
@@ -610,9 +609,11 @@ def upload(self, file_name: str):
 
     @retry(wait=wait_exponential(multiplier=2, min=3, max=6),
            stop=stop_after_attempt(3),
-           retry=(retry_if_exception_type(GCError) | retry_if_exception_type(IOError)))
+           retry=(retry_if_exception_type(Exception)))
     def __download_file(self, file_id, path, filename, mime_type):
-        request = self.__service.files().get_media(fileId=file_id)
+        request = self.__service.files().get_media(
+                      fileId=file_id,
+                      supportsAllDrives=True)
         filename = filename.replace('/', '')
         if len(filename.encode()) > 255:
             ext = os.path.splitext(filename)[1]
@@ -753,7 +754,7 @@ def __receive_callback(self, request_id, response, exception):
             if response['files']:
                 self.response[request_id] = response
 
-    def __drive_query(self, DRIVE_IDS, search_type, file_name):
+    def __drive_query(self, drive_ids, search_type, file_name):
         batch = self.__service.new_batch_http_request(self.__receive_callback)
         query = f"name contains '{file_name}' and "
         if search_type is not None:
@@ -762,7 +763,7 @@ def __drive_query(self, DRIVE_IDS, search_type, file_name):
             elif search_type == '-f':
                 query += "mimeType != 'application/vnd.google-apps.folder' and "
         query += "trashed=false"
-        for drive_id in DRIVE_IDS:
+        for drive_id in drive_ids:
             if drive_id == "root":
                 batch.add(
                     self.__service.files().list(
diff --git a/bot/helper/ext_utils/fs_utils.py b/bot/helper/ext_utils/fs_utils.py
index ea3bff4f..e7aef7fb 100644
--- a/bot/helper/ext_utils/fs_utils.py
+++ b/bot/helper/ext_utils/fs_utils.py
@@ -67,7 +67,7 @@ def get_path_size(path: str):
 
 def get_base_name(orig_path: str):
     ext = [ext for ext in ARCH_EXT if orig_path.lower().endswith(ext)]
-    if len(ext) > 0:
+    if ext:
         ext = ext[0]
         return re.split(ext + '$', orig_path, maxsplit=1, flags=re.I)[0]
     else:
diff --git a/bot/helper/telegram_helper/button_builder.py b/bot/helper/telegram_helper/button_builder.py
index e31d0d24..863c821f 100644
--- a/bot/helper/telegram_helper/button_builder.py
+++ b/bot/helper/telegram_helper/button_builder.py
@@ -3,22 +3,22 @@
 class ButtonMaker:
 
     def __init__(self):
-        self.button = []
-        self.header_button = []
-        self.footer_button = []
+        self.__button = []
+        self.__header_button = []
+        self.__footer_button = []
 
-    def build_button(self, key, link, footer=False, header=False):
-        if not footer and not header:
-            self.button.append(InlineKeyboardButton(text=key, url=link))
-        elif header:
-            self.header_button.append(InlineKeyboardButton(text=key, url=link))
-        elif footer:
-            self.footer_button.append(InlineKeyboardButton(text=key, url=link))
+    def build_button(self, key, link, position=None):
+        if not position:
+            self.__button.append(InlineKeyboardButton(text=key, url=link))
+        elif position == 'header':
+            self.__header_button.append(InlineKeyboardButton(text=key, url=link))
+        elif position == 'footer':
+            self.__footer_button.append(InlineKeyboardButton(text=key, url=link))
 
     def build_menu(self, n_cols):
-        menu = [self.button[i:i + n_cols] for i in range(0, len(self.button), n_cols)]
-        if self.header_button:
-            menu.insert(0, self.header_button)
-        if self.footer_button:
-            menu.append(self.footer_button)
+        menu = [self.__button[i:i + n_cols] for i in range(0, len(self.__button), n_cols)]
+        if self.__header_button:
+            menu.insert(0, self.__header_button)
+        if self.__footer_button:
+            menu.append(self.__footer_button)
         return InlineKeyboardMarkup(menu)
diff --git a/bot/modules/auth.py b/bot/modules/auth.py
index a4755154..450a8246 100644
--- a/bot/modules/auth.py
+++ b/bot/modules/auth.py
@@ -10,7 +10,7 @@ def authorize(update, context):
     user_id = ''
     reply_message = update.message.reply_to_message
     if len(context.args) == 1:
-        user_id = int(context.args[0])
+        user_id = context.args[0]
     elif reply_message:
         user_id = reply_message.from_user.id
     if user_id:
@@ -38,7 +38,7 @@ def unauthorize(update, context):
     user_id = ''
     reply_message = update.message.reply_to_message
     if len(context.args) == 1:
-        user_id = int(context.args[0])
+        user_id = context.args[0]
     elif reply_message:
         user_id = reply_message.from_user.id
     if user_id:
diff --git a/bot/modules/eval.py b/bot/modules/eval.py
index f5d481e9..9456f787 100644
--- a/bot/modules/eval.py
+++ b/bot/modules/eval.py
@@ -4,13 +4,11 @@
 
 from contextlib import redirect_stdout
 from io import StringIO, BytesIO
-from telegram import ParseMode
 from telegram.ext import CommandHandler
 
 from bot import dispatcher
 from bot.helper.telegram_helper.bot_commands import BotCommands
 from bot.helper.telegram_helper.filters import CustomFilters
-from bot.helper.telegram_helper.message_utils import sendMessage
 
 namespaces = {}
 
@@ -36,7 +34,7 @@ def send(msg, bot, update):
         bot.send_message(
             chat_id=update.effective_chat.id,
             text=f"`{msg}`",
-            parse_mode=ParseMode.MARKDOWN)
+            parse_mode='MARKDOWN')
 
 def evaluate(update, context):
     bot = context.bot
diff --git a/bot/modules/shell.py b/bot/modules/shell.py
index c6428ddf..4fc91ca5 100644
--- a/bot/modules/shell.py
+++ b/bot/modules/shell.py
@@ -31,9 +31,9 @@ def shell(update, context):
                 reply_to_message_id=message.message_id,
                 chat_id=message.chat_id)
     elif len(reply) != 0:
-        message.reply_text(reply, parse_mode='HTML')
+        message.reply_text(reply, parse_mode='MARKDOWN')
     else:
-        message.reply_text('<b>Command executed</b>', parse_mode='HTML')
+        message.reply_text('<b>Command executed</b>', parse_mode='MARKDOWN')
 
 shell_handler = CommandHandler(BotCommands.ShellCommand, shell,
                                filters=CustomFilters.owner_filter, run_async=True)