diff --git a/README.md b/README.md
index f0db147..5bc401f 100644
--- a/README.md
+++ b/README.md
@@ -19,6 +19,7 @@
 | array | [🔊](https://dict.youdao.com/dictvoice?audio=array&type=1)  /ə'rei/ | [🔊](https://dict.youdao.com/dictvoice?audio=array&type=2)  /əˈreɪ/ |  ❌ /æ'rei/ |
 | ASCII | [🔊](https://dict.youdao.com/dictvoice?audio=ascii&type=1)  /'æski/ | [🔊](https://dict.youdao.com/dictvoice?audio=ascii&type=2)  /ˈæski/ |  ❌ /ɑːsk/ |
 | aspect | [🔊](https://dict.youdao.com/dictvoice?audio=aspect&type=1)  /'æspekt/ | [🔊](https://dict.youdao.com/dictvoice?audio=aspect&type=2)  /ˈæspekt/ |  ❌ /ə'spekt/ |
+| async | [🔊](https://dict.youdao.com/dictvoice?audio=async&type=1) /əˈsɪŋk/ | [🔊](https://dict.youdao.com/dictvoice?audio=async&type=2) /æˈsɪŋk/ | ❌ /'æsɪŋk/ |
 | avatar | [🔊](https://dict.youdao.com/dictvoice?audio=avatar&type=1)  /'ævətɑː/ | [🔊](https://dict.youdao.com/dictvoice?audio=avatar&type=2)  /ˈævətɑːr/ |  ❌ /ə'vʌtɑ/ |
 | Azure | [🔊](https://dict.youdao.com/dictvoice?audio=azure&type=1)  /'æʒə/ | [🔊](https://dict.youdao.com/dictvoice?audio=azure&type=2)  /ˈæʒər/ |  ❌ /ˈæzʊʒə/ |
 | bind | [🔊](https://dict.youdao.com/dictvoice?audio=bind&type=1)  /baɪnd/ | [🔊](https://dict.youdao.com/dictvoice?audio=bind&type=2)  /baɪnd/ |  ❌ /bɪnd/ |
diff --git a/tools/addword.py b/tools/addword.py
index d96ae32..21a0050 100755
--- a/tools/addword.py
+++ b/tools/addword.py
@@ -4,11 +4,12 @@
 Create the description for a word to be added to the word list
 Usage: addword.py <word>
 """
-import sys
 import re
+import sys
 import urllib.request
 from bs4 import BeautifulSoup
 
+
 def main():
     """Generate the information with pronunciations for a word to be added to the word list"""
     if len(sys.argv) != 2:
@@ -16,34 +17,36 @@ def main():
         sys.exit(1)
     word = sys.argv[1]
     pronunciations = get_pronunciations(word)
-    britsh_en = '[🔊](' + pronunciations[0][0] +')' + ' ' + '/' + pronunciations[0][1] + '/'
-    american_en = '[🔊](' + pronunciations[1][0] +')' + ' ' + '/' + pronunciations[1][1] + '/'
+    britsh_en = '[🔊](' + pronunciations[0][0] + ')' + ' ' + '/' + pronunciations[0][1] + '/'
+    american_en = '[🔊](' + pronunciations[1][0] + ')' + ' ' + '/' + pronunciations[1][1] + '/'
     line = '| ' + word + ' | ' + britsh_en + ' | ' + american_en + ' | ' + ' ' + '|'
     print(line)
 
+
 def get_pronunciations(word):
     """Return the word's pronouciation URLs and phonetic transcriptions
        from youdao.com if available"""
     word = word.strip()
-    word_url = "https://dict.youdao.com/w/en/"+word
-    pron_url = "https://dict.youdao.com/dictvoice?audio="+word+"&"
+    word_url = 'https://dict.youdao.com/w/en/' + word
+    pron_url = 'https://dict.youdao.com/dictvoice?audio='+ word + '&'
     britsh_en = [" ", " "]
-    american_en = [" "," "]
+    american_en = [" ", " "]
     try:
         response = urllib.request.urlopen(word_url).read()
-        soup = BeautifulSoup(response, "html.parser")
-        spans = soup.find_all('span', {'class' : 'pronounce'})
+        soup = BeautifulSoup(response, 'html.parser')
+        spans = soup.find_all('span', {'class': 'pronounce'})
         lines = [span.get_text() for span in spans]
         match = re.findall(r'\[.+\]', lines[0])
-        britsh_en[0] = pron_url + "type=1"
+        britsh_en[0] = pron_url + 'type=1'
         britsh_en[1] = match[0].replace('[', '').replace(']', '')
         match = re.findall(r'\[.+\]', lines[1])
-        american_en[0] = pron_url + "type=2"
+        american_en[0] = pron_url + 'type=2'
         american_en[1] = match[0].replace('[', '').replace(']', '')
     except:
         return britsh_en, american_en
 
     return britsh_en, american_en
 
+
 if __name__ == '__main__':
     main()