diff --git a/README.md b/README.md
index 20ceb0a..a19a0f4 100644
--- a/README.md
+++ b/README.md
@@ -118,4 +118,4 @@ A list of ideas and TODO. Don't hesitate to give feedback on the ones you really
 
 ## Issues ?
 
-* Remove the watermarks on pdf files => done, some warning in okular on generated pdf, but seems ok. Seems to be a bug in PyPDF2.
+* Remove the watermarks on pdf files => done, some warning in okular on generated pdf, but seems ok. Seems to be a bug in Okular.
diff --git a/fetcher.py b/fetcher.py
index 3e77bef..6048305 100644
--- a/fetcher.py
+++ b/fetcher.py
@@ -57,9 +57,10 @@ def findISBN(src):
                                   stdout=subprocess.PIPE,
                                   stderr=subprocess.PIPE,
                                   bufsize=1)
-    while totext.poll() == None:
+    while totext.poll() is None:
         extractfull = totext.stdin.readline()
-        extractISBN = isbn_re.search(extractfull.lower().replace('Œ', '-'))
+        extractISBN = isbn_re.search(extractfull.lower().replace('Œ',
+                                                                 '-'))
         if extractISBN:
             totext.terminate()
             break
@@ -111,7 +112,7 @@ def findDOI(src):
                                   stdout=subprocess.PIPE,
                                   stderr=subprocess.PIPE)
 
-    while totext.poll() == None:
+    while totext.poll() is None:
         extractfull = totext.stdin.readline()
         extractDOI = doi_re.search(extractfull.lower().replace('Œ', '-'))
         if not extractDOI: