n encoded to the underlying file using file_encoding. The intermediate data type will usually be Unicode but depends on the specified codecs. Bytes read from the file are decoded using file_encoding and then passed back to the caller encoded using data_encoding. If file_encoding is not given, it defaults to data_encoding. errors may be given to define the error handling. It defaults to 'strict' which causes ValueErrors to be raised in case an encoding error occurs. The returned wrapped file object provides two extra attributes .data_encoding and .file_encoding which reflect the given parameters of the same name. The attributes can be used for introspection by Python programs. N)r