text: """RFC 2822 message manipulation.
  
  Note: This is only a very rough sketch of a full RFC-822 parser; in particular
  the tokenizing of addresses does not adhere to all the quoting rules.
  
  Note: RFC 2822 is a long awaited update to RFC 822.  This module should
  conform to RFC 2822, and is thus mis-named (it's not worth renaming it).  Some
  effort at RFC 2822 updates have been made, but a thorough audit has not been
  performed.  Consider any RFC 2822 non-conformance to be a bug.
  
      RFC 2822: http://www.faqs.org/rfcs/rfc2822.html
      RFC 822 : http://www.faqs.org/rfcs/rfc822.html (obsolete)
  
  Directions for use:
  
  To create a Message object: first open a file, e.g.:
  
    fp = open(file, 'r')
  
  You can use any other legal way of getting an open file object, e.g. use
  sys.stdin or call os.popen().  Then pass the open file object to the Message()
  constructor:
  
    m = Message(fp)
  
  This class can work with any input object that supports a readline method.  If
  the input object has seek and tell capability, the rewindbody method will
  work; also illegal lines will be pushed back onto the input stream.  If the
  input object lacks seek but has an `unread' method that can push back a line
  of input, Message will use that to push back illegal lines.  Thus this class
  can be used to parse messages coming from a buffered stream.
  
  The optional `seekable' argument is provided as a workaround for certain stdio
  libraries in which tell() discards buffered data before discovering that the
  lseek() system call doesn't work.  For maximum portability, you should set the
  seekable argument to zero to prevent that initial \code{tell} when passing in
  an unseekable object such as a a file object created from a socket object.  If
  it is 1 on entry -- which it is by default -- the tell() method of the open
  file object is called once; if this raises an exception, seekable is reset to
  0.  For other nonzero values of seekable, this test is not made.
  
  To get the text of a particular header there are several methods:
  
    str = m.getheader(name)
    str = m.getrawheader(name)
  
  where name is the name of the header, e.g. 'Subject'.  The difference is that
  getheader() strips the leading and trailing whitespace, while getrawheader()
  doesn't.  Both functions retain embedded whitespace (including newlines)
  exactly as they are specified in the header, and leave the case of the text
  unchanged.
  
  For addresses and address lists there are functions
  
    realname, mailaddress = m.getaddr(name)
    list = m.getaddrlist(name)
  
  where the latter returns a list of (realname, mailaddr) tuples.
  
  There is also a method
  
    time = m.getdate(name)
  
  which parses a Date-like field and returns a time-compatible tuple,
  i.e. a tuple such as returned by time.localtime() or accepted by
  time.mktime().
  
  See the class definition for lower level access methods.
  
  There are also some utility functions here.
  """
  # Cleanup and extensions by Eric S. Raymond <esr@thyrsus.com>
  
  import time
  
  from warnings import warnpy3k
  warnpy3k("in 3.x, rfc822 has been removed in favor of the email package",
           stacklevel=2)
  
  __all__ = ["Message","AddressList","parsedate","parsedate_tz","mktime_tz"]
  
  _blanklines = ('\r\n', '\n')            # Optimization for islast()
  
  
  class Message:
      """Represents a single RFC 2822-compliant message."""
  
      def __init__(self, fp, seekable = 1):
          """Initialize the class instance and read the headers."""
          if seekable == 1:
              # Exercise tell() to make sure it works
              # (and then assume seek() works, too)
              try:
                  fp.tell()
              except (AttributeError, IOError):
                  seekable = 0
          self.fp = fp
          self.seekable = seekable
          self.startofheaders = None
          self.startofbody = None
          #
          if self.seekable:
              try:
                  self.startofheaders = self.fp.tell()
              except IOError:
                  self.seekable = 0
          #
          self.readheaders()
          #
          if self.seekable:
              try:
                  self.startofbody = self.fp.tell()
              except IOError:
                  self.seekable = 0
  
      def rewindbody(self):
          """Rewind the file to the start of the body (if seekable)."""
          if not self.seekable:
              raise IOError, "unseekable file"
          self.fp.seek(self.startofbody)
  
      def readheaders(self):
          """Read header lines.
  
          Read header lines up to the entirely blank line that terminates them.
          The (normally blank) line that ends the headers is skipped, but not
          included in the returned list.  If a non-header line ends the headers,
          (which is an error), an attempt is made to backspace over it; it is
          never included in the returned list.
  
          The variable self.status is set to the empty string if all went well,
          otherwise it is an error message.  The variable self.headers is a
          completely uninterpreted list of lines contained in the header (so
          printing them will reproduce the header exactly as it appears in the
          file).
          """
          self.dict = {}
          self.unixfrom = ''
          self.headers = lst = []
          self.status = ''
          headerseen = ""
          firstline = 1
          startofline = unread = tell = None
          if hasattr(self.fp, 'unread'):
              unread = self.fp.unread
          elif self.seekable:
              tell = self.fp.tell
          while 1:
              if tell:
                  try:
                      startofline = tell()
                  except IOError:
                      startofline = tell = None
                      self.seekable = 0
              line = self.fp.readline()
              if not line:
                  self.status = 'EOF in headers'
                  break
              # Skip unix From name time lines
              if firstline and line.startswith('From '):
                  self.unixfrom = self.unixfrom + line
                  continue
              firstline = 0
              if headerseen and line[0] in ' \t':
                  # It's a continuation line.
                  lst.append(line)
                  x = (self.dict[headerseen] + "\n " + line.strip())
                  self.dict[headerseen] = x.strip()
                  continue
              elif self.iscomment(line):
                  # It's a comment.  Ignore it.
                  continue
              elif self.islast(line):
                  # Note! No pushback here!  The delimiter line gets eaten.
                  break
              headerseen = self.isheader(line)
              if headerseen:
                  # It's a legal header line, save it.
                  lst.append(line)
                  self.dict[headerseen] = line[len(headerseen)+1:].strip()
                  continue
              else:
                  # It's not a header line; throw it back and stop here.
                  if not self.dict:
                      self.status = 'No headers'
                  else:
                      self.status = 'Non-header line where header expected'
                  # Try to undo the read.
                  if unread:
                      unread(line)
                  elif tell:
                      self.fp.seek(startofline)
                  else:
                      self.status = self.status + '; bad seek'
                  break
  
      def isheader(self, line):
          """Determine whether a given line is a legal header.
  
          This method should return the header name, suitably canonicalized.
          You may override this method in order to use Message parsing on tagged
          data in RFC 2822-like formats with special header formats.
          """
          i = line.find(':')
          if i > 0:
              return line[:i].lower()
          return None
  
      def islast(self, line):
          """Determine whether a line is a legal end of RFC 2822 headers.
  
          You may override this method if your application wants to bend the
          rules, e.g. to strip trailing whitespace, or to recognize MH template
          separators ('--------').  For convenience (e.g. for code reading from
          sockets) a line consisting of \r\n also matches.
          """
          return line in _blanklines
  
      def iscomment(self, line):
          """Determine whether a line should be skipped entirely.
  
          You may override this method in order to use Message parsing on tagged
          data in RFC 2822-like formats that support embedded comments or
          free-text data.
          """
          return False
  
      def getallmatchingheaders(self, name):
          """Find all header lines matching a given header name.
  
          Look through the list of headers and find all lines matching a given
          header name (and their continuation lines).  A list of the lines is
          returned, without interpretation.  If the header does not occur, an
          empty list is returned.  If the header occurs multiple times, all
          occurrences are returned.  Case is not important in the header name.
          """
          name = name.lower() + ':'
          n = len(name)
          lst = []
          hit = 0
          for line in self.headers:
              if line[:n].lower() == name:
                  hit = 1
              elif not line[:1].isspace():
                  hit = 0
              if hit:
                  lst.append(line)
          return lst
  
      def getfirstmatchingheader(self, name):
          """Get the first header line matching name.
  
          This is similar to getallmatchingheaders, but it returns only the
          first matching header (and its continuation lines).
          """
          name = name.lower() + ':'
          n = len(name)
          lst = []
          hit = 0
          for line in self.headers:
              if hit:
                  if not line[:1].isspace():
                      break
              elif line[:n].lower() == name:
                  hit = 1
              if hit:
                  lst.append(line)
          return lst
  
      def getrawheader(self, name):
          """A higher-level interface to getfirstmatchingheader().
  
          Return a string containing the literal text of the header but with the
          keyword stripped.  All leading, trailing and embedded whitespace is
          kept in the string, however.  Return None if the header does not
          occur.
          """
  
          lst = self.getfirstmatchingheader(name)
          if not lst:
              return None
          lst[0] = lst[0][len(name) + 1:]
          return ''.join(lst)
  
      def getheader(self, name, default=None):
          """Get the header value for a name.
  
          This is the normal interface: it returns a stripped version of the
          header value for a given header name, or None if it doesn't exist.
          This uses the dictionary version which finds the *last* such header.
          """
          return self.dict.get(name.lower(), default)
      get = getheader
  
      def getheaders(self, name):
          """Get all values for a header.
  
          This returns a list of values for headers given more than once; each
          value in the result list is stripped in the same way as the result of
          getheader().  If the header is not given, return an empty list.
          """
          result = []
          current = ''
          have_header = 0
          for s in self.getallmatchingheaders(name):
              if s[0].isspace():
                  if current:
                      current = "%s\n %s" % (current, s.strip())
                  else:
                      current = s.strip()
              else:
                  if have_header:
                      result.append(current)
                  current = s[s.find(":") + 1:].strip()
                  have_header = 1
          if have_header:
              result.append(current)
          return result
  
      def getaddr(self, name):
          """Get a single address from a header, as a tuple.
  
          An example return value:
          ('Guido van Rossum', 'guido@cwi.nl')
          """
          # New, by Ben Escoto
          alist = self.getaddrlist(name)
          if alist:
              return alist[0]
          else:
              return (None, None)
  
      def getaddrlist(self, name):
          """Get a list of addresses from a header.
  
          Retrieves a list of addresses from a header, where each address is a
          tuple as returned by getaddr().  Scans all named headers, so it works
          properly with multiple To: or Cc: headers for example.
          """
          raw = []
          for h in self.getallmatchingheaders(name):
              if h[0] in ' \t':
                  raw.append(h)
              else:
                  if raw:
                      raw.append(', ')
                  i = h.find(':')
                  if i > 0:
                      addr = h[i+1:]
                  raw.append(addr)
          alladdrs = ''.join(raw)
          a = AddressList(alladdrs)
          return a.addresslist
  
      def getdate(self, name):
          """Retrieve a date field from a header.
  
          Retrieves a date field from the named header, returning a tuple
          compatible with time.mktime().
          """
          try:
              data = self[name]
          except KeyError:
              return None
          return parsedate(data)
  
      def getdate_tz(self, name):
          """Retrieve a date field from a header as a 10-tuple.
  
          The first 9 elements make up a tuple compatible with time.mktime(),
          and the 10th is the offset of the poster's time zone from GMT/UTC.
          """
          try:
              data = self[name]
          except KeyError:
              return None
          return parsedate_tz(data)
  
  
      # Access as a dictionary (only finds *last* header of each type):
  
      def __len__(self):
          """Get the number of headers in a message."""
          return len(self.dict)
  
      def __getitem__(self, name):
          """Get a specific header, as from a dictionary."""
          return self.dict[name.lower()]
  
      def __setitem__(self, name, value):
          """Set the value of a header.
  
          Note: This is not a perfect inversion of __getitem__, because any
          changed headers get stuck at the end of the raw-headers list rather
          than where the altered header was.
          """
          del self[name] # Won't fail if it doesn't exist
          self.dict[name.lower()] = value
          text = name + ": " + value
          for line in text.split("\n"):
              self.headers.append(line + "\n")
  
      def __delitem__(self, name):
          """Delete all occurrences of a specific header, if it is present."""
          name = name.lower()
          if not name in self.dict:
              return
          del self.dict[name]
          name = name + ':'
          n = len(name)
          lst = []
          hit = 0
          for i in range(len(self.headers)):
              line = self.headers[i]
              if line[:n].lower() == name:
                  hit = 1
              elif not line[:1].isspace():
                  hit = 0
              if hit:
                  lst.append(i)
          for i in reversed(lst):
              del self.headers[i]
  
      def setdefault(self, name, default=""):
          lowername = name.lower()
          if lowername in self.dict:
              return self.dict[lowername]
          else:
              text = name + ": " + default
              for line in text.split("\n"):
                  self.headers.append(line + "\n")
              self.dict[lowername] = default
              return default
  
      def has_key(self, name):
          """Determine whether a message contains the named header."""
          return name.lower() in self.dict
  
      def __contains__(self, name):
          """Determine whether a message contains the named header."""
          return name.lower() in self.dict
  
      def __iter__(self):
          return iter(self.dict)
  
      def keys(self):
          """Get all of a message's header field names."""
          return self.dict.keys()
  
      def values(self):
          """Get all of a message's header field values."""
          return self.dict.values()
  
      def items(self):
          """Get all of a message's headers.
  
          Returns a list of name, value tuples.
          """
          return self.dict.items()
  
      def __str__(self):
          return ''.join(self.headers)
  
  
  # Utility functions
  # -----------------
  
  # XXX Should fix unquote() and quote() to be really conformant.
  # XXX The inverses of the parse functions may also be useful.
  
  
  def unquote(s):
      """Remove quotes from a string."""
      if len(s) > 1:
          if s.startswith('"') and s.endswith('"'):
              return s[1:-1].replace('\\\\', '\\').replace('\\"', '"')
          if s.startswith('<') and s.endswith('>'):
              return s[1:-1]
      return s
  
  
  def quote(s):
      """Add quotes around a string."""
      return s.replace('\\', '\\\\').replace('"', '\\"')
  
  
  def parseaddr(address):
      """Parse an address into a (realname, mailaddr) tuple."""
      a = AddressList(address)
      lst = a.addresslist
      if not lst:
          return (None, None)
      return lst[0]
  
  
  class AddrlistClass:
      """Address parser class by Ben Escoto.
  
      To understand what this class does, it helps to have a copy of
      RFC 2822 in front of you.
  
      http://www.faqs.org/rfcs/rfc2822.html
  
      Note: this class interface is deprecated and may be removed in the future.
      Use rfc822.AddressList instead.
      """
  
      def __init__(self, field):
          """Initialize a new instance.
  
          `field' is an unparsed address header field, containing one or more
          addresses.
          """
          self.specials = '()<>@,:;.\"[]'
          self.pos = 0
          self.LWS = ' \t'
          self.CR = '\r\n'
          self.atomends = self.specials + self.LWS + self.CR
          # Note that RFC 2822 now specifies `.' as obs-phrase, meaning that it
          # is obsolete syntax.  RFC 2822 requires that we recognize obsolete
          # syntax, so allow dots in phrases.
          self.phraseends = self.atomends.replace('.', '')
          self.field = field
          self.commentlist = []
  
      def gotonext(self):
          """Parse up to the start of the next address."""
          while self.pos < len(self.field):
              if self.field[self.pos] in self.LWS + '\n\r':
                  self.pos = self.pos + 1
              elif self.field[self.pos] == '(':
                  self.commentlist.append(self.getcomment())
              else: break
  
      def getaddrlist(self):
          """Parse all addresses.
  
          Returns a list containing all of the addresses.
          """
          result = []
          ad = self.getaddress()
          while ad:
              result += ad
              ad = self.getaddress()
          return result
  
      def getaddress(self):
          """Parse the next address."""
          self.commentlist = []
          self.gotonext()
  
          oldpos = self.pos
          oldcl = self.commentlist
          plist = self.getphraselist()
  
          self.gotonext()
          returnlist = []
  
          if self.pos >= len(self.field):
              # Bad email address technically, no domain.
              if plist:
                  returnlist = [(' '.join(self.commentlist), plist[0])]
  
          elif self.field[self.pos] in '.@':
              # email address is just an addrspec
              # this isn't very efficient since we start over
              self.pos = oldpos
              self.commentlist = oldcl
              addrspec = self.getaddrspec()
              returnlist = [(' '.join(self.commentlist), addrspec)]
  
          elif self.field[self.pos] == ':':
              # address is a group
              returnlist = []
  
              fieldlen = len(self.field)
              self.pos += 1
              while self.pos < len(self.field):
                  self.gotonext()
                  if self.pos < fieldlen and self.field[self.pos] == ';':
                      self.pos += 1
                      break
                  returnlist = returnlist + self.getaddress()
  
          elif self.field[self.pos] == '<':
              # Address is a phrase then a route addr
              routeaddr = self.getrouteaddr()
  
              if self.commentlist:
                  returnlist = [(' '.join(plist) + ' (' + \
                           ' '.join(self.commentlist) + ')', routeaddr)]
              else: returnlist = [(' '.join(plist), routeaddr)]
  
          else:
              if plist:
                  returnlist = [(' '.join(self.commentlist), plist[0])]
              elif self.field[self.pos] in self.specials:
                  self.pos += 1
  
          self.gotonext()
          if self.pos < len(self.field) and self.field[self.pos] == ',':
              self.pos += 1
          return returnlist
  
      def getrouteaddr(self):
          """Parse a route address (Return-path value).
  
          This method just skips all the route stuff and returns the addrspec.
          """
          if self.field[self.pos] != '<':
              return
  
          expectroute = 0
          self.pos += 1
          self.gotonext()
          adlist = ""
          while self.pos < len(self.field):
              if expectroute:
                  self.getdomain()
                  expectroute = 0
              elif self.field[self.pos] == '>':
                  self.pos += 1
                  break
              elif self.field[self.pos] == '@':
                  self.pos += 1
                  expectroute = 1
              elif self.field[self.pos] == ':':
                  self.pos += 1
              else:
                  adlist = self.getaddrspec()
                  self.pos += 1
                  break
              self.gotonext()
  
          return adlist
  
      def getaddrspec(self):
          """Parse an RFC 2822 addr-spec."""
          aslist = []
  
          self.gotonext()
          while self.pos < len(self.field):
              if self.field[self.pos] == '.':
                  aslist.append('.')
                  self.pos += 1
              elif self.field[self.pos] == '"':
                  aslist.append('"%s"' % self.getquote())
              elif self.field[self.pos] in self.atomends:
                  break
              else: aslist.append(self.getatom())
              self.gotonext()
  
          if self.pos >= len(self.field) or self.field[self.pos] != '@':
              return ''.join(aslist)
  
          aslist.append('@')
          self.pos += 1
          self.gotonext()
          return ''.join(aslist) + self.getdomain()
  
      def getdomain(self):
          """Get the complete domain name from an address."""
          sdlist = []
          while self.pos < len(self.field):
              if self.field[self.pos] in self.LWS:
                  self.pos += 1
              elif self.field[self.pos] == '(':
                  self.commentlist.append(self.getcomment())
              elif self.field[self.pos] == '[':
                  sdlist.append(self.getdomainliteral())
              elif self.field[self.pos] == '.':
                  self.pos += 1
                  sdlist.append('.')
              elif self.field[self.pos] in self.atomends:
                  break
              else: sdlist.append(self.getatom())
          return ''.join(sdlist)
  
      def getdelimited(self, beginchar, endchars, allowcomments = 1):
          """Parse a header fragment delimited by special characters.
  
          `beginchar' is the start character for the fragment.  If self is not
          looking at an instance of `beginchar' then getdelimited returns the
          empty string.
  
          `endchars' is a sequence of allowable end-delimiting characters.
          Parsing stops when one of these is encountered.
  
          If `allowcomments' is non-zero, embedded RFC 2822 comments are allowed
          within the parsed fragment.
          """
          if self.field[self.pos] != beginchar:
              return ''
  
          slist = ['']
          quote = 0
          self.pos += 1
          while self.pos < len(self.field):
              if quote == 1:
                  slist.append(self.field[self.pos])
                  quote = 0
              elif self.field[self.pos] in endchars:
                  self.pos += 1
                  break
              elif allowcomments and self.field[self.pos] == '(':
                  slist.append(self.getcomment())
                  continue        # have already advanced pos from getcomment
              elif self.field[self.pos] == '\\':
                  quote = 1
              else:
                  slist.append(self.field[self.pos])
              self.pos += 1
  
          return ''.join(slist)
  
      def getquote(self):
          """Get a quote-delimited fragment from self's field."""
          return self.getdelimited('"', '"\r', 0)
  
      def getcomment(self):
          """Get a parenthesis-delimited fragment from self's field."""
          return self.getdelimited('(', ')\r', 1)
  
      def getdomainliteral(self):
          """Parse an RFC 2822 domain-literal."""
          return '[%s]' % self.getdelimited('[', ']\r', 0)
  
      def getatom(self, atomends=None):
          """Parse an RFC 2822 atom.
  
          Optional atomends specifies a different set of end token delimiters
          (the default is to use self.atomends).  This is used e.g. in
          getphraselist() since phrase endings must not include the `.' (which
          is legal in phrases)."""
          atomlist = ['']
          if atomends is None:
              atomends = self.atomends
  
          while self.pos < len(self.field):
              if self.field[self.pos] in atomends:
                  break
              else: atomlist.append(self.field[self.pos])
              self.pos += 1
  
          return ''.join(atomlist)
  
      def getphraselist(self):
          """Parse a sequence of RFC 2822 phrases.
  
          A phrase is a sequence of words, which are in turn either RFC 2822
          atoms or quoted-strings.  Phrases are canonicalized by squeezing all
          runs of continuous whitespace into one space.
          """
          plist = []
  
          while self.pos < len(self.field):
              if self.field[self.pos] in self.LWS:
                  self.pos += 1
              elif self.field[self.pos] == '"':
                  plist.append(self.getquote())
              elif self.field[self.pos] == '(':
                  self.commentlist.append(self.getcomment())
              elif self.field[self.pos] in self.phraseends:
                  break
              else:
                  plist.append(self.getatom(self.phraseends))
  
          return plist
  
  class AddressList(AddrlistClass):
      """An AddressList encapsulates a list of parsed RFC 2822 addresses."""
      def __init__(self, field):
          AddrlistClass.__init__(self, field)
          if field:
              self.addresslist = self.getaddrlist()
          else:
              self.addresslist = []
  
      def __len__(self):
          return len(self.addresslist)
  
      def __str__(self):
          return ", ".join(map(dump_address_pair, self.addresslist))
  
      def __add__(self, other):
          # Set union
          newaddr = AddressList(None)
          newaddr.addresslist = self.addresslist[:]
          for x in other.addresslist:
              if not x in self.addresslist:
                  newaddr.addresslist.append(x)
          return newaddr
  
      def __iadd__(self, other):
          # Set union, in-place
          for x in other.addresslist:
              if not x in self.addresslist:
                  self.addresslist.append(x)
          return self
  
      def __sub__(self, other):
          # Set difference
          newaddr = AddressList(None)
          for x in self.addresslist:
              if not x in other.addresslist:
                  newaddr.addresslist.append(x)
          return newaddr
  
      def __isub__(self, other):
          # Set difference, in-place
          for x in other.addresslist:
              if x in self.addresslist:
                  self.addresslist.remove(x)
          return self
  
      def __getitem__(self, index):
          # Make indexing, slices, and 'in' work
          return self.addresslist[index]
  
  def dump_address_pair(pair):
      """Dump a (name, address) pair in a canonicalized form."""
      if pair[0]:
          return '"' + pair[0] + '" <' + pair[1] + '>'
      else:
          return pair[1]
  
  # Parse a date field
  
  _monthnames = ['jan', 'feb', 'mar', 'apr', 'may', 'jun', 'jul',
                 'aug', 'sep', 'oct', 'nov', 'dec',
                 'january', 'february', 'march', 'april', 'may', 'june', 'july',
                 'august', 'september', 'october', 'november', 'december']
  _daynames = ['mon', 'tue', 'wed', 'thu', 'fri', 'sat', 'sun']
  
  # The timezone table does not include the military time zones defined
  # in RFC822, other than Z.  According to RFC1123, the description in
  # RFC822 gets the signs wrong, so we can't rely on any such time
  # zones.  RFC1123 recommends that numeric timezone indicators be used
  # instead of timezone names.
  
  _timezones = {'UT':0, 'UTC':0, 'GMT':0, 'Z':0,
                'AST': -400, 'ADT': -300,  # Atlantic (used in Canada)
                'EST': -500, 'EDT': -400,  # Eastern
                'CST': -600, 'CDT': -500,  # Central
                'MST': -700, 'MDT': -600,  # Mountain
                'PST': -800, 'PDT': -700   # Pacific
                }
  
  
  def parsedate_tz(data):
      """Convert a date string to a time tuple.
  
      Accounts for military timezones.
      """
      if not data:
          return None
      data = data.split()
      if data[0][-1] in (',', '.') or data[0].lower() in _daynames:
          # There's a dayname here. Skip it
          del data[0]
      else:
          # no space after the "weekday,"?
          i = data[0].rfind(',')
          if i >= 0:
              data[0] = data[0][i+1:]
      if len(data) == 3: # RFC 850 date, deprecated
          stuff = data[0].split('-')
          if len(stuff) == 3:
              data = stuff + data[1:]
      if len(data) == 4:
          s = data[3]
          i = s.find('+')
          if i > 0:
              data[3:] = [s[:i], s[i+1:]]
          else:
              data.append('') # Dummy tz
      if len(data) < 5:
          return None
      data = data[:5]
      [dd, mm, yy, tm, tz] = data
      mm = mm.lower()
      if not mm in _monthnames:
          dd, mm = mm, dd.lower()
          if not mm in _monthnames:
              return None
      mm = _monthnames.index(mm)+1
      if mm > 12: mm = mm - 12
      if dd[-1] == ',':
          dd = dd[:-1]
      i = yy.find(':')
      if i > 0:
          yy, tm = tm, yy
      if yy[-1] == ',':
          yy = yy[:-1]
      if not yy[0].isdigit():
          yy, tz = tz, yy
      if tm[-1] == ',':
          tm = tm[:-1]
      tm = tm.split(':')
      if len(tm) == 2:
          [thh, tmm] = tm
          tss = '0'
      elif len(tm) == 3:
          [thh, tmm, tss] = tm
      else:
          return None
      try:
          yy = int(yy)
          dd = int(dd)
          thh = int(thh)
          tmm = int(tmm)
          tss = int(tss)
      except ValueError:
          return None
      tzoffset = None
      tz = tz.upper()
      if tz in _timezones:
          tzoffset = _timezones[tz]
      else:
          try:
              tzoffset = int(tz)
          except ValueError:
              pass
      # Convert a timezone offset into seconds ; -0500 -> -18000
      if tzoffset:
          if tzoffset < 0:
              tzsign = -1
              tzoffset = -tzoffset
          else:
              tzsign = 1
          tzoffset = tzsign * ( (tzoffset//100)*3600 + (tzoffset % 100)*60)
      return (yy, mm, dd, thh, tmm, tss, 0, 1, 0, tzoffset)
  
  
  def parsedate(data):
      """Convert a time string to a time tuple."""
      t = parsedate_tz(data)
      if t is None:
          return t
      return t[:9]
  
  
  def mktime_tz(data):
      """Turn a 10-tuple as returned by parsedate_tz() into a UTC timestamp."""
      if data[9] is None:
          # No zone info, so localtime is better assumption than GMT
          return time.mktime(data[:8] + (-1,))
      else:
          t = time.mktime(data[:8] + (0,))
          return t - data[9] - time.timezone
  
  def formatdate(timeval=None):
      """Returns time format preferred for Internet standards.
  
      Sun, 06 Nov 1994 08:49:37 GMT  ; RFC 822, updated by RFC 1123
  
      According to RFC 1123, day and month names must always be in
      English.  If not for that, this code could use strftime().  It
      can't because strftime() honors the locale and could generated
      non-English names.
      """
      if timeval is None:
          timeval = time.time()
      timeval = time.gmtime(timeval)
      return "%s, %02d %s %04d %02d:%02d:%02d GMT" % (
              ("Mon", "Tue", "Wed", "Thu", "Fri", "Sat", "Sun")[timeval[6]],
              timeval[2],
              ("Jan", "Feb", "Mar", "Apr", "May", "Jun",
               "Jul", "Aug", "Sep", "Oct", "Nov", "Dec")[timeval[1]-1],
                                  timeval[0], timeval[3], timeval[4], timeval[5])
  
  
  # When used as script, run a small test program.
  # The first command line argument must be a filename containing one
  # message in RFC-822 format.
  
  if __name__ == '__main__':
      import sys, os
      file = os.path.join(os.environ['HOME'], 'Mail/inbox/1')
      if sys.argv[1:]: file = sys.argv[1]
      f = open(file, 'r')
      m = Message(f)
      print 'From:', m.getaddr('from')
      print 'To:', m.getaddrlist('to')
      print 'Subject:', m.getheader('subject')
      print 'Date:', m.getheader('date')
      date = m.getdate_tz('date')
      tz = date[-1]
      date = time.localtime(mktime_tz(date))
      if date:
          print 'ParsedDate:', time.asctime(date),
          hhmmss = tz
          hhmm, ss = divmod(hhmmss, 60)
          hh, mm = divmod(hhmm, 60)
          print "%+03d%02d" % (hh, mm),
          if ss: print ".%02d" % ss,
          print
      else:
          print 'ParsedDate:', None
      m.rewindbody()
      n = 0
      while f.readline():
          n += 1
      print 'Lines:', n
      print '-'*70
      print 'len =', len(m)
      if 'Date' in m: print 'Date =', m['Date']
      if 'X-Nonsense' in m: pass
      print 'keys =', m.keys()
      print 'values =', m.values()
      print 'items =', m.items()
  