email.header.decode_header(header) Decode a message header value without converting the character set. The header value is in

__setitem__(name, val) Add a header to the message with field name name and value val. The field is appended

attach(payload) Add the given payload to the current payload, which must be None or a list of Message

refold_source If the value for a header in the Message object originated from a

add_flag(flag) Set the flag(s) specified by flag without changing other flags. To add more than one flag at a time

get_string(key) Return a string representation of the message corresponding to key, or raise a

remove(key) __delitem__(key) discard(key) These methods immediately

mimetypes.guess_extension(type, strict=True) Guess the extension for a file based on its MIME type, given by type.

set_labels(labels) Set the list of labels on the message to labels.

get_visible() Return an Message instance whose headers are the message’s visible headers and whose body is empty