diff --git a/src/calibre/ebooks/metadata/mobi.py b/src/calibre/ebooks/metadata/mobi.py
index ac675b1d84..5b45722383 100644
--- a/src/calibre/ebooks/metadata/mobi.py
+++ b/src/calibre/ebooks/metadata/mobi.py
@@ -265,7 +265,7 @@ class MetadataUpdater(object):
 
         # Pad to a 4-byte boundary
         trail = len(new_record0.getvalue()) % 4
-        pad = '\0' * (4 - trail) # Always pad w/ at least 1 byte
+        pad = '\0' * (4 - trail)  # Always pad w/ at least 1 byte
         new_record0.write(pad)
         new_record0.write('\0'*(1024*8))
 
@@ -278,7 +278,8 @@ class MetadataUpdater(object):
     def hexdump(self, src, length=16):
         # Diagnostic
         FILTER=''.join([(len(repr(chr(x)))==3) and chr(x) or '.' for x in range(256)])
-        N=0; result=''
+        N=0
+        result=''
         while src:
             s,src = src[:length],src[length:]
             hexa = ' '.join(["%02X"%ord(x) for x in s])
@@ -292,7 +293,7 @@ class MetadataUpdater(object):
         for i in xrange(self.nrecs):
             offset, a1,a2,a3,a4 = unpack('>LBBBB', self.data[78+i*8:78+i*8+8])
             flags, val = a1, a2<<16|a3<<8|a4
-            pdbrecords.append( [offset, flags, val] )
+            pdbrecords.append([offset, flags, val])
         return pdbrecords
 
     def update_pdbrecords(self, updated_pdbrecords):
@@ -422,7 +423,7 @@ class MetadataUpdater(object):
             exth.write(data)
         exth = exth.getvalue()
         trail = len(exth) % 4
-        pad = '\0' * (4 - trail) # Always pad w/ at least 1 byte
+        pad = '\0' * (4 - trail)  # Always pad w/ at least 1 byte
         exth = ['EXTH', pack('>II', len(exth) + 12, len(recs)), exth, pad]
         exth = ''.join(exth)
 
@@ -474,7 +475,6 @@ def get_metadata(stream):
     except ImportError:
         import Image as PILImage
 
-
     stream.seek(0)
     try:
         raw = stream.read(3)
@@ -530,5 +530,3 @@ def get_metadata(stream):
         im.convert('RGB').save(obuf, format='JPEG')
         mi.cover_data = ('jpg', obuf.getvalue())
     return mi
-
-