将标头添加到多个文件

Question

我有三个不同的.txt文件，在每个文件中，我想添加一个不同的标头。例如：line1="rain", add line to file 1;line2="cap", add line to file 2;line3="different", add line to file 3;

我尝试编写一个函数writing_to_files，该函数可以简化操作，但是我对如何添加行的内容有疑问。

def writing_to_files(filename, header_names):
    '''recovers file and writes a line in the file'''
    with file(filename, 'r') as original:
        data=original.read()
        with file(filename, 'w') as modified:
            modified.write(header_names + "\n" + data)
    return True