## 11.12.1 Message Objects

A `Message` instance has the following methods:

`rewindbody` ()
  Seek to the start of the message body. This only works if the file object is seekable.

`getallmatchingheaders` (name)
  Return a list of lines consisting of all headers matching name, if any. Each physical line, whether it is a continuation line or not, is a separate list item. Return the empty list if no header matches name.

`getfirstmatchingheader` (name)
  Return a list of lines comprising the first header matching name, and its continuation line(s), if any. Return `None` if there is no header matching name.

`getrawheader` (name)
  Return a single string consisting of the text after the colon in the first header matching name. This includes leading whitespace, the trailing linefeed, and internal linefeeds and whitespace if there any continuation line(s) were present. Return `None` if there is no header matching name.

`getheader` (name)
  Like `getrawheader(name)`, but strip leading and trailing whitespace (but not internal whitespace).

`getaddr` (name)
  Return a pair (full name, email address) parsed from the string returned by `getheader(name)`. If no header matching name exists, return `None, None`; otherwise both the full name and the address are (possibly empty )strings.

  Example: If `m`'s first `From` header contains the string
  `'jack@cwi.nl (Jack Jansen)'`, then `m.getaddr('From')` will yield the pair `('Jack Jansen', 'jack@cwi.nl')`. If the header contained `'Jack Jansen <jack@cwi.nl>'` instead, it would yield the exact same result.

`getaddrlist` (name)
  This is similar to `getaddr(list)`, but parses a header containing a list of email addresses (e.g. a `To` header) and returns a list of (full name, email address) pairs (even if there was only one address in the header). If there is no header matching name, return an empty list.

  XXX The current version of this function is not really correct. It yields bogus results if a full name contains a comma.

`getdate` (name)
  Retrieve a header using `getheader` and parse it into a 9-tuple compatible with `time.mktime()`. If there is no header matching name, or it is unparsable, return `None`.

  Date parsing appears to be a black art, and not all mailers adhere to the standard. While it has been tested and found correct on a large collection of email from many sources, it is still possible that this function may occasionally yield an incorrect result.

`getdate_tz` (name)
  Retrieve a header using `getheader` and parse it into a 10-tuple; the first 9 elements will make a tuple compatible with `time.mktime()`, and the 10th is a number giving the offset of the date's time zone from UTC. Similarly to `getdate()`, if there is no header matching name, or it is unparsable, return `None`.

`Message` instances also support a read-only mapping interface. In particular: `m[name]` is the same as `m.getheader(name)`; and `len(m)`, `m.has_key(name)`, `m.keys()`, `m.values()` and `m.items()` act as expected (and consistently).

Finally, `Message` instances have two public instance variables:

`headers`
  A list containing the entire set of header lines, in the order in which they were read. Each line contains a trailing newline. The blank line terminating the headers is not contained in the list.

`fp`
  The file object passed at instantiation time.