diff --git a/cps/epub.py b/cps/epub.py
index 8d0b2817..6473d401 100644
--- a/cps/epub.py
+++ b/cps/epub.py
@@ -7,12 +7,13 @@ import os
 import uploader
 from iso639 import languages as isoLanguages
 
-def extractCover(zip, coverFile, coverpath, tmp_file_name):
+
+def extractCover(zipFile, coverFile, coverpath, tmp_file_name):
     if coverFile is None:
         return None
     else:
         zipCoverPath = os.path.join(coverpath , coverFile).replace('\\','/')
-        cf = zip.read(zipCoverPath)
+        cf = zipFile.read(zipCoverPath)
         prefix = os.path.splitext(tmp_file_name)[0]
         tmp_cover_name = prefix + '.' + os.path.basename(zipCoverPath)
         image = open(tmp_cover_name, 'wb')
@@ -28,15 +29,15 @@ def get_epub_info(tmp_file_path, original_file_name, original_file_extension):
         'dc': 'http://purl.org/dc/elements/1.1/'
     }
 
-    zip = zipfile.ZipFile(tmp_file_path)
+    epubZip = zipfile.ZipFile(tmp_file_path)
 
-    txt = zip.read('META-INF/container.xml')
+    txt = epubZip.read('META-INF/container.xml')
     tree = etree.fromstring(txt)
     cfname = tree.xpath('n:rootfiles/n:rootfile/@full-path', namespaces=ns)[0]
-    cf = zip.read(cfname)
+    cf = epubZip.read(cfname)
     tree = etree.fromstring(cf)
 
-    coverpath=os.path.dirname(cfname)
+    coverpath = os.path.dirname(cfname)
 
     p = tree.xpath('/pkg:package/pkg:metadata', namespaces=ns)[0]
 
@@ -70,23 +71,23 @@ def get_epub_info(tmp_file_path, original_file_name, original_file_extension):
     coversection = tree.xpath("/pkg:package/pkg:manifest/pkg:item[@id='cover-image']/@href", namespaces=ns)
     coverfile = None
     if len(coversection) > 0:
-        coverfile = extractCover(zip, coversection[0], coverpath, tmp_file_path)
+        coverfile = extractCover(epubZip, coversection[0], coverpath, tmp_file_path)
     else:
         meta_cover = tree.xpath("/pkg:package/pkg:metadata/pkg:meta[@name='cover']/@content", namespaces=ns)
         if len(meta_cover) > 0:
             coversection = tree.xpath("/pkg:package/pkg:manifest/pkg:item[@id='"+meta_cover[0]+"']/@href", namespaces=ns)
             if len(coversection) > 0:
-                filetype = coversection[0].rsplit('.',1)[-1]
-                if filetype == "xhtml" or filetype == "html": #if cover is (x)html format
-                    markup = zip.read(os.path.join(coverpath,coversection[0]))
+                filetype = coversection[0].rsplit('.', 1)[-1]
+                if filetype == "xhtml" or filetype == "html":  #if cover is (x)html format
+                    markup = epubZip.read(os.path.join(coverpath, coversection[0]))
                     markupTree = etree.fromstring(markup)
-                    #no matter xhtml or html with no namespace
+                    # no matter xhtml or html with no namespace
                     imgsrc = markupTree.xpath("//*[local-name() = 'img']/@src")
-                    #imgsrc maybe startwith "../"" so fullpath join then relpath to cwd
+                    # imgsrc maybe startwith "../"" so fullpath join then relpath to cwd
                     filename = os.path.relpath(os.path.join(os.path.dirname(os.path.join(coverpath, coversection[0])), imgsrc[0]))
-                    coverfile = extractCover(zip, filename, "", tmp_file_path)
+                    coverfile = extractCover(epubZip, filename, "", tmp_file_path)
                 else:
-                    coverfile = extractCover(zip, coversection[0], coverpath, tmp_file_path)
+                    coverfile = extractCover(epubZip, coversection[0], coverpath, tmp_file_path)
 
     if epub_metadata['title'] is None:
         title = original_file_name
diff --git a/cps/helper.py b/cps/helper.py
index 577fa826..7f561319 100755
--- a/cps/helper.py
+++ b/cps/helper.py
@@ -43,9 +43,9 @@ import web
 
 try:
     import unidecode
-    use_unidecode=True
+    use_unidecode = True
 except Exception as e:
-    use_unidecode=False
+    use_unidecode = False
 
 # Global variables
 global_task = None
@@ -242,7 +242,7 @@ def get_valid_filename(value, replace_whitespace=True):
     Returns the given string converted to a string that can be used for a clean
     filename. Limits num characters to 128 max.
     """
-    if value[-1:] ==u'.':
+    if value[-1:] == u'.':
         value = value[:-1]+u'_'
     if use_unidecode:
         value=(unidecode.unidecode(value)).strip()
@@ -266,7 +266,7 @@ def get_sorted_author(value):
     regexes = ["^(JR|SR)\.?$","^I{1,3}\.?$","^IV\.?$"]
     combined = "(" + ")|(".join(regexes) + ")"
     value = value.split(" ")
-    if re.match(combined,value[-1].upper()):
+    if re.match(combined, value[-1].upper()):
         value2 = value[-2] + ", " + " ".join(value[:-2]) + " " + value[-1]
     else:
         value2 = value[-1] + ", " + " ".join(value[:-1])
@@ -295,6 +295,7 @@ def update_dir_stucture(book_id, calibrepath):
         book.path = new_authordir + '/' + book.path.split('/')[1]
     db.session.commit()
 
+
 def update_dir_structure_gdrive(book_id):
     db.session.connection().connection.connection.create_function("title_sort", 1, db.title_sort)
     book = db.session.query(db.Books).filter(db.Books.id == book_id).first()
@@ -313,7 +314,7 @@ def update_dir_structure_gdrive(book_id):
     
     if authordir != new_authordir:
         gFile=gd.getFileFromEbooksFolder(web.Gdrive.Instance().drive,None,authordir)
-        gFile['title']= new_authordir
+        gFile['title'] = new_authordir
         gFile.Upload()
         book.path = new_authordir + '/' + book.path.split('/')[1]
 
@@ -327,23 +328,23 @@ class Updater(threading.Thread):
 
     def run(self):
         global global_task
-        self.status=1
+        self.status = 1
         r = requests.get('https://api.github.com/repos/janeczku/calibre-web/zipball/master', stream=True)
         fname = re.findall("filename=(.+)", r.headers['content-disposition'])[0]
-        self.status=2
+        self.status = 2
         z = zipfile.ZipFile(StringIO(r.content))
-        self.status=3
+        self.status = 3
         tmp_dir = gettempdir()
         z.extractall(tmp_dir)
-        self.status=4
+        self.status = 4
         self.update_source(os.path.join(tmp_dir,os.path.splitext(fname)[0]),ub.config.get_main_dir)
-        self.status=5
+        self.status = 5
         global_task = 0
         db.session.close()
         db.engine.dispose()
         ub.session.close()
         ub.engine.dispose()
-        self.status=6
+        self.status = 6
 
         if web.gevent_server:
             web.gevent_server.stop()
@@ -351,7 +352,7 @@ class Updater(threading.Thread):
             # stop tornado server
             server = IOLoop.instance()
             server.add_callback(server.stop)
-        self.status=7
+        self.status = 7
 
     def get_update_status(self):
         return self.status
@@ -431,8 +432,8 @@ class Updater(threading.Thread):
         # destination files
         old_list = list()
         exclude = (
-        'vendor' + os.sep + 'kindlegen.exe', 'vendor' + os.sep + 'kindlegen', os.sep + 'app.db',
-            os.sep + 'vendor',os.sep + 'calibre-web.log')
+            'vendor' + os.sep + 'kindlegen.exe', 'vendor' + os.sep + 'kindlegen', os.sep + 'app.db',
+            os.sep + 'vendor', os.sep + 'calibre-web.log')
         for root, dirs, files in os.walk(destination, topdown=True):
             for name in files:
                 old_list.append(os.path.join(root, name).replace(destination, ''))
@@ -462,7 +463,7 @@ class Updater(threading.Thread):
             else:
                 try:
                     logging.getLogger('cps.web').debug("Delete file " + item_path)
-                    log_from_thread("Delete file " + item_path)
+                    # log_from_thread("Delete file " + item_path)
                     os.remove(item_path)
                 except Exception:
                     logging.getLogger('cps.web').debug("Could not remove:" + item_path)
diff --git a/cps/translations/zh_Hans_CN/LC_MESSAGES/messages.mo b/cps/translations/zh_Hans_CN/LC_MESSAGES/messages.mo
index b02c863b..0a73aa40 100644
Binary files a/cps/translations/zh_Hans_CN/LC_MESSAGES/messages.mo and b/cps/translations/zh_Hans_CN/LC_MESSAGES/messages.mo differ
diff --git a/cps/translations/zh_Hans_CN/LC_MESSAGES/messages.po b/cps/translations/zh_Hans_CN/LC_MESSAGES/messages.po
index 7c4d6361..f131c5a6 100644
--- a/cps/translations/zh_Hans_CN/LC_MESSAGES/messages.po
+++ b/cps/translations/zh_Hans_CN/LC_MESSAGES/messages.po
@@ -307,7 +307,7 @@ msgstr "用户 '%(user)s' 已被创建"
 
 #: cps/web.py:2198
 msgid "Found an existing account for this email address or nickname."
-msgstr "已找到使用此邮箱或昵称的账号。"
+msgstr "已存在使用此邮箱或昵称的账号。"
 
 #: cps/web.py:2220
 msgid "Mail settings updated"
@@ -496,7 +496,7 @@ msgstr "最新提交时间戳"
 
 #: cps/templates/admin.html:83
 msgid "Reconnect to Calibre DB"
-msgstr ""
+msgstr "重新连接到Calibre数据库"
 
 #: cps/templates/admin.html:84
 msgid "Restart Calibre-web"
@@ -590,7 +590,7 @@ msgstr "编辑后查看书籍"
 
 #: cps/templates/book_edit.html:107 cps/templates/book_edit.html:118
 msgid "Get metadata"
-msgstr ""
+msgstr "获取元数据"
 
 #: cps/templates/book_edit.html:108 cps/templates/config_edit.html:117
 #: cps/templates/login.html:19 cps/templates/search_form.html:79
@@ -600,11 +600,11 @@ msgstr "提交"
 
 #: cps/templates/book_edit.html:121
 msgid "Keyword"
-msgstr ""
+msgstr "关键字"
 
 #: cps/templates/book_edit.html:122
 msgid " Search keyword "
-msgstr ""
+msgstr "搜索关键字"
 
 #: cps/templates/book_edit.html:124 cps/templates/layout.html:60
 msgid "Go!"
@@ -612,32 +612,32 @@ msgstr "走起！"
 
 #: cps/templates/book_edit.html:125
 msgid "Click the cover to load metadata to the form"
-msgstr ""
+msgstr "点击封面加载元数据到表单"
 
 #: cps/templates/book_edit.html:129 cps/templates/book_edit.html:142
 msgid "Loading..."
-msgstr ""
+msgstr "加载中..."
 
 #: cps/templates/book_edit.html:132
 msgid "Close"
-msgstr ""
+msgstr "关闭"
 
 #: cps/templates/book_edit.html:143
 msgid "Search error!"
-msgstr ""
+msgstr "搜索错误"
 
 #: cps/templates/book_edit.html:144
 msgid "No Result! Please try anonther keyword."
-msgstr ""
+msgstr "没有结果!请尝试别的关键字."
 
 #: cps/templates/book_edit.html:146 cps/templates/detail.html:76
 #: cps/templates/search_form.html:14
 msgid "Publisher"
-msgstr ""
+msgstr "出版社"
 
 #: cps/templates/book_edit.html:148
 msgid "Source"
-msgstr ""
+msgstr "来源"
 
 #: cps/templates/config_edit.html:7
 msgid "Location of Calibre database"
@@ -645,7 +645,7 @@ msgstr "Calibre 数据库位置"
 
 #: cps/templates/config_edit.html:13
 msgid "Use google drive?"
-msgstr ""
+msgstr "是否使用google drive?"
 
 #: cps/templates/config_edit.html:17
 msgid "Client id"
@@ -660,8 +660,8 @@ msgid "Calibre Base URL"
 msgstr ""
 
 #: cps/templates/config_edit.html:29
-msgid "Google drive Calibre folder"
-msgstr ""
+msgid "Google drive Calibre folde"
+msgstr "Google drive Calibre 文件夹"
 
 #: cps/templates/config_edit.html:38
 msgid "Metadata Watch Channel ID"
@@ -843,12 +843,12 @@ msgstr "显示随机书籍"
 #: cps/templates/index.xml:43 cps/templates/index.xml:47
 #: cps/templates/layout.html:132
 msgid "Read Books"
-msgstr ""
+msgstr "已读书籍"
 
 #: cps/templates/index.xml:50 cps/templates/index.xml:54
 #: cps/templates/layout.html:133
 msgid "Unread Books"
-msgstr ""
+msgstr "未读书籍"
 
 #: cps/templates/index.xml:57 cps/templates/layout.html:144
 msgid "Authors"
@@ -1082,7 +1082,7 @@ msgstr "显示作者选择"
 
 #: cps/templates/user_edit.html:75
 msgid "Show read and unread"
-msgstr ""
+msgstr "显示已读和未读"
 
 #: cps/templates/user_edit.html:79
 msgid "Show random books in detail view"
diff --git a/cps/web.py b/cps/web.py
index cf259af9..b455c520 100755
--- a/cps/web.py
+++ b/cps/web.py
@@ -131,6 +131,7 @@ class Singleton:
     def __instancecheck__(self, inst):
         return isinstance(inst, self._decorated)
 
+
 @Singleton
 class Gauth:
     def __init__(self):
@@ -567,7 +568,7 @@ def feed_index():
 @app.route("/opds/osd")
 @requires_basic_auth_if_no_ano
 def feed_osd():
-    xml = render_title_template('osd.xml',lang='de-DE')
+    xml = render_title_template('osd.xml', lang='de-DE')
     response = make_response(xml)
     response.headers["Content-Type"] = "application/xml"
     return response
@@ -1466,7 +1467,7 @@ def advanced_search():
             try:
                 cur_l = LC.parse(lang.lang_code)
                 lang.name = cur_l.get_language_name(get_locale())
-            except Exception as e:
+            except Exception:
                 lang.name = _(isoLanguages.get(part3=lang.lang_code).name)
     else:
         languages = None