diff --git a/src/calibre/ebooks/lrf/html/convert_from.py b/src/calibre/ebooks/lrf/html/convert_from.py
index be4feb2aeb..4bbf1fc53e 100644
--- a/src/calibre/ebooks/lrf/html/convert_from.py
+++ b/src/calibre/ebooks/lrf/html/convert_from.py
@@ -152,16 +152,16 @@ class HTMLConverter(object):
                      (re.compile('<hr>', re.IGNORECASE),
                       lambda match : '<span style="page-break-after:always"> </span>'),
                      # Create header tags
-                     (re.compile('<h2[^><]*?id=BookTitle[^><]*?(align=)*(?(1)(\\w+))*[^><]*?>[^><]*?</h2>', re.IGNORECASE),
+                     (re.compile(r'<h2[^><]*?id=BookTitle[^><]*?(align=)*(?(1)(\w+))*[^><]*?>[^><]*?</h2>', re.IGNORECASE),
                       lambda match : '<h1 id="BookTitle" align="%s">%s</h1>'%(match.group(2) if match.group(2) else 'center', match.group(3))),
-                     (re.compile('<h2[^><]*?id=BookAuthor[^><]*?(align=)*(?(1)(\\w+))*[^><]*?>[^><]*?</h2>', re.IGNORECASE),
+                     (re.compile(r'<h2[^><]*?id=BookAuthor[^><]*?(align=)*(?(1)(\w+))*[^><]*?>[^><]*?</h2>', re.IGNORECASE),
                       lambda match : '<h2 id="BookAuthor" align="%s">%s</h2>'%(match.group(2) if match.group(2) else 'center', match.group(3))),
-                     (re.compile('<span[^><]*?id=title[^><]*?>(.*?)</span>', re.IGNORECASE|re.DOTALL),
+                     (re.compile(r'<span[^><]*?id=title[^><]*?>(.*?)</span>', re.IGNORECASE|re.DOTALL),
                       lambda match : '<h2 class="title">%s</h2>'%(match.group(1),)),
-                     (re.compile('<span[^><]*?id=subtitle[^><]*?>(.*?)</span>', re.IGNORECASE|re.DOTALL),
+                     (re.compile(r'<span[^><]*?id=subtitle[^><]*?>(.*?)</span>', re.IGNORECASE|re.DOTALL),
                       lambda match : '<h3 class="subtitle">%s</h3>'%(match.group(1),)),
                      # Blank lines
-                     (re.compile('<div[^><]*?>(&nbsp;){4}</div>', re.IGNORECASE),
+                     (re.compile(r'<div[^><]*?>(&nbsp;){4}</div>', re.IGNORECASE),
                       lambda match : '<p></p>'),
                      ]
 
@@ -403,7 +403,7 @@ class HTMLConverter(object):
         selector name and the value is a dictionary of properties
         """
         sdict, pdict = {}, {}
-        style = re.sub('/\\*.*?\\*/', '', style)  # Remove /*...*/ comments
+        style = re.sub(r'/\*.*?\*/', '', style)  # Remove /*...*/ comments
         for sel in re.findall(HTMLConverter.SELECTOR_PAT, style):
             for key in sel[0].split(','):
                 val = self.parse_style_properties(sel[1])
diff --git a/src/calibre/ebooks/lrf/pylrs/pylrf.py b/src/calibre/ebooks/lrf/pylrs/pylrf.py
index 21bdb18afc..ba793e50ed 100644
--- a/src/calibre/ebooks/lrf/pylrs/pylrf.py
+++ b/src/calibre/ebooks/lrf/pylrs/pylrf.py
@@ -492,9 +492,8 @@ class LrfFileStream(LrfStreamBase):
 
     def __init__(self, streamFlags, filename):
         LrfStreamBase.__init__(self, streamFlags)
-        f = open(filename, "rb")
-        self.streamData = f.read()
-        f.close()
+        with open(filename, "rb") as f:
+            self.streamData = f.read()
 
 
 class LrfObject(object):