x=res=x.encode() (res(res)) m=res.decode() (m)
(==) f: data=f.read() (data)
(=) f: f.seek() f.write()
(==) f1: msg=f1.read() new_msg=msg.replace() (==) f2: f2.write(new_msg) os (==) read_f\ (==) write_f: line read_f: write_f.write(line.replace()) os.remove() os.rename()