MergeFiles.py

import os

path = "C:\downloads"
keyword=".cl"
merged_file_name="merged_file"+keyword

def backtrace(path, l, content, suffix):
    for i in l:
        path_i=path+"\\"+i
        print path_i
        if os.path.isdir(path_i):
            content = backtrace(path_i, os.listdir(path_i), content, keyword)
        if os.path.isfile(path_i):
            if i.find(keyword)>0 and i!=merged_file_name:
                with open(path_i, 'r') as content_file:
                    # change the style of merged string
                    content += "\n\n\n=======\n"+path_i+"\n=======\n"
                    content += content_file.read()
    return content

content=backtrace(path, os.listdir(path), "", keyword)
f = open(merged_file_name, 'w')
f.write(content)
print "finished"