def auto_version_url(file_path):
file_md5 = "<STR_LIT>"<EOL>try:<EOL><INDENT>file_md5 = md5(open(cfg.get('<STR_LIT>') +<EOL>os.sep + file_path).read()).hexdigest()<EOL><DEDENT>except IOError:<EOL><INDENT>pass<EOL><DEDENT>return file_path + "<STR_LIT>" % file_md5<EOL>
Appends modification time of the file to the request URL in order for the
        browser to refresh the cache when file changes

        @param file_path: path to the file, e.g js/foo.js
        @return: file_path with modification time appended to URL