diff --git a/header.sh b/header.sh
new file mode 100644
index 0000000..edf040f
--- /dev/null
+++ b/header.sh
@@ -0,0 +1,63 @@
+#!/bin/bash
+#'''
+#    File name: header.sh
+#    Author: xdtianyu@gmail.com
+#    Date created: 2015-01-07 14:24:16
+#    Date last modified: 2015-01-09 15:19:31
+#    Bash Version: 4.3.11(1)-release
+#'''
+ 
+AUTHOR="xdtianyu@gmail.com"
+PYTHON_VERSION=$(python -c 'import sys; print(sys.version[:5])')
+ 
+for file in $(ls *.py); do
+    echo "check $file ..."
+    MODIFIED=$(stat -c %y $file| cut -d'.' -f1)
+    #echo "Last modified: $MODIFIED"
+    CURRENT_DATE=$(date "+%Y-%m-%d %H:%M:%S")
+    AUTHOR_COUNT=$(cat "$file" |grep "    Author:" |wc -l)
+    if [ $AUTHOR_COUNT  -gt 1 ];then
+        echo "More than one author, skip."
+        continue
+    elif [ $AUTHOR_COUNT -eq 1 ];then
+        echo "Have author, check modified date."
+        ORI=$(cat $file |grep "    Date last modified: ")
+        if [ "$ORI" == "" ];then
+            echo "no line"
+            continue
+        fi
+        TARGET="    Date last modified: ${MODIFIED}"
+        #echo $ORI
+        #echo $TARGET
+        if [ "$ORI" == "$TARGET" ];then
+            echo "No change detected."
+        else
+            if [ $(cat $file |grep "    Date last modified: "|wc -l) -gt 1 ];then
+                echo "More than one \"Date last modified\" detected, skip"
+                continue
+            fi
+            LINE=$(cat $file |grep "    Date last modified: " -n | cut -d':' -f1)
+            sed -i "${LINE}s/.*/    Date last modified: ${CURRENT_DATE}/" $file
+        fi
+        # Check file name
+        FILE_COUNT=$(cat $file |grep "    File name:"|wc -l)
+        if [ $FILE_COUNT -gt 1 ];then
+            echo "More than one \"File name\" detecetd, skip"
+            continue
+        elif [ $FILE_COUNT -eq 1 ];then
+            echo "Check file name..."
+            ORI_FILE_NAME=$(cat $file |grep "    File name:")
+            TARGET_FILE_NAME="    File name: $file"
+            if [ ! "$ORI_FILE_NAME" == "$TARGET_FILE_NAME" ];then
+                echo "File name changed, update now"
+                FILE_LINE=$(cat $file |grep "    File name: " -n | cut -d':' -f1)
+                sed -i "${FILE_LINE}s/.*/${TARGET_FILE_NAME}/" $file
+            else
+                echo "No change detected."
+            fi
+        fi
+    else
+        echo "Have no author, add header."
+        sed -i "1s/^/\'\'\'\n    File name: $file\n    Author: $AUTHOR\n    Date created: $MODIFIED\n    Date last modified: $CURRENT_DATE\n    Python Version: $PYTHON_VERSION\n\'\'\'\n\n/" $file
+    fi
+done