diff --git a/songbook_core/build.py b/songbook_core/build.py
index 330ae6a3..b4a77be4 100644
--- a/songbook_core/build.py
+++ b/songbook_core/build.py
@@ -5,7 +5,6 @@
 
 import codecs
 import glob
-import logging
 import os.path
 import re
 import subprocess
@@ -61,7 +60,8 @@ class Songbook(object):
         self.songslist = None
         self._parse(raw_songbook)
 
-    def _set_songs_default(self, config):
+    @staticmethod
+    def _set_songs_default(config):
         """Set the default values for the Song() class.
 
         Argument:
diff --git a/songbook_core/errors.py b/songbook_core/errors.py
index 448814f9..6b850712 100644
--- a/songbook_core/errors.py
+++ b/songbook_core/errors.py
@@ -13,7 +13,7 @@ class SongbookError(Exception):
 class TemplateError(SongbookError):
     """Error during template generation"""
 
-    def __init__(self, original, message = None):
+    def __init__(self, original, message=None):
         super(TemplateError, self).__init__()
         self.original = original
         self.message = message