diff --git a/src/caosadvancedtools/pandoc_header_tools.py b/src/caosadvancedtools/pandoc_header_tools.py
index 6322da7ea71bba8e261f33f8e8a1d260e2971d6d..4c6dfb21836f4e960fadd084336f053edbc4be41 100644
--- a/src/caosadvancedtools/pandoc_header_tools.py
+++ b/src/caosadvancedtools/pandoc_header_tools.py
@@ -45,6 +45,7 @@ class NoValidHeader(Exception):
                "using -f option".format(filename))
         super().__init__(msg, *args, **kwargs)
 
+
 class MetadataFileMissing(Exception):
 
     def __init__(self, filename, *args, **kwargs):
@@ -52,6 +53,7 @@ class MetadataFileMissing(Exception):
         msg = "Metadata file README.md missing in " + filename
         super().__init__(msg, *args, **kwargs)
 
+
 class ParseErrorsInHeader(Exception):
     def __init__(self, filename, reason, *args, **kwargs):
         self.filename = filename
@@ -59,6 +61,7 @@ class ParseErrorsInHeader(Exception):
         msg = "Invalid header in {}. Reason: {}".format(filename, reason)
         super().__init__(msg, *args, **kwargs)
 
+
 TEMPLATEHEADER = """
 ---
 responsible:
@@ -185,7 +188,6 @@ def save_header(filename, header_data):
         f.writelines(textlines)
 
 
-
 def add_header(filename, header_dict=None):
     """
     Add a header to an md file.
@@ -195,10 +197,10 @@ def add_header(filename, header_dict=None):
     If header_dict is a dictionary and not None the header
     will be created based on the keys and values of that dictionary.
     """
-    
+
     if os.path.isdir(filename):
         filename = os.path.join(filename, "README.md")
-        
+
     if os.path.exists(filename):
         with open(filename) as f:
             textlines = f.readlines()
diff --git a/src/caosadvancedtools/read_md_header.py b/src/caosadvancedtools/read_md_header.py
index 514117a42361cb43cf56ecceed3b708577e5e937..ece81c403af7ca65fb48ebd457fdded8544413e8 100644
--- a/src/caosadvancedtools/read_md_header.py
+++ b/src/caosadvancedtools/read_md_header.py
@@ -27,6 +27,7 @@
 
 from . import pandoc_header_tools
 
+
 def get_header(fn):
     return pandoc_header_tools.get_header(fn)[2]