jpayne@68: # Copyright (C) 2002-2007 Python Software Foundation
jpayne@68: # Contact: email-sig@python.org
jpayne@68: 
jpayne@68: """Email address parsing code.
jpayne@68: 
jpayne@68: Lifted directly from rfc822.py.  This should eventually be rewritten.
jpayne@68: """
jpayne@68: 
jpayne@68: __all__ = [
jpayne@68:     'mktime_tz',
jpayne@68:     'parsedate',
jpayne@68:     'parsedate_tz',
jpayne@68:     'quote',
jpayne@68:     ]
jpayne@68: 
jpayne@68: import time, calendar
jpayne@68: 
jpayne@68: SPACE = ' '
jpayne@68: EMPTYSTRING = ''
jpayne@68: COMMASPACE = ', '
jpayne@68: 
jpayne@68: # Parse a date field
jpayne@68: _monthnames = ['jan', 'feb', 'mar', 'apr', 'may', 'jun', 'jul',
jpayne@68:                'aug', 'sep', 'oct', 'nov', 'dec',
jpayne@68:                'january', 'february', 'march', 'april', 'may', 'june', 'july',
jpayne@68:                'august', 'september', 'october', 'november', 'december']
jpayne@68: 
jpayne@68: _daynames = ['mon', 'tue', 'wed', 'thu', 'fri', 'sat', 'sun']
jpayne@68: 
jpayne@68: # The timezone table does not include the military time zones defined
jpayne@68: # in RFC822, other than Z.  According to RFC1123, the description in
jpayne@68: # RFC822 gets the signs wrong, so we can't rely on any such time
jpayne@68: # zones.  RFC1123 recommends that numeric timezone indicators be used
jpayne@68: # instead of timezone names.
jpayne@68: 
jpayne@68: _timezones = {'UT':0, 'UTC':0, 'GMT':0, 'Z':0,
jpayne@68:               'AST': -400, 'ADT': -300,  # Atlantic (used in Canada)
jpayne@68:               'EST': -500, 'EDT': -400,  # Eastern
jpayne@68:               'CST': -600, 'CDT': -500,  # Central
jpayne@68:               'MST': -700, 'MDT': -600,  # Mountain
jpayne@68:               'PST': -800, 'PDT': -700   # Pacific
jpayne@68:               }
jpayne@68: 
jpayne@68: 
jpayne@68: def parsedate_tz(data):
jpayne@68:     """Convert a date string to a time tuple.
jpayne@68: 
jpayne@68:     Accounts for military timezones.
jpayne@68:     """
jpayne@68:     res = _parsedate_tz(data)
jpayne@68:     if not res:
jpayne@68:         return
jpayne@68:     if res[9] is None:
jpayne@68:         res[9] = 0
jpayne@68:     return tuple(res)
jpayne@68: 
jpayne@68: def _parsedate_tz(data):
jpayne@68:     """Convert date to extended time tuple.
jpayne@68: 
jpayne@68:     The last (additional) element is the time zone offset in seconds, except if
jpayne@68:     the timezone was specified as -0000.  In that case the last element is
jpayne@68:     None.  This indicates a UTC timestamp that explicitly declaims knowledge of
jpayne@68:     the source timezone, as opposed to a +0000 timestamp that indicates the
jpayne@68:     source timezone really was UTC.
jpayne@68: 
jpayne@68:     """
jpayne@68:     if not data:
jpayne@68:         return
jpayne@68:     data = data.split()
jpayne@68:     # The FWS after the comma after the day-of-week is optional, so search and
jpayne@68:     # adjust for this.
jpayne@68:     if data[0].endswith(',') or data[0].lower() in _daynames:
jpayne@68:         # There's a dayname here. Skip it
jpayne@68:         del data[0]
jpayne@68:     else:
jpayne@68:         i = data[0].rfind(',')
jpayne@68:         if i >= 0:
jpayne@68:             data[0] = data[0][i+1:]
jpayne@68:     if len(data) == 3: # RFC 850 date, deprecated
jpayne@68:         stuff = data[0].split('-')
jpayne@68:         if len(stuff) == 3:
jpayne@68:             data = stuff + data[1:]
jpayne@68:     if len(data) == 4:
jpayne@68:         s = data[3]
jpayne@68:         i = s.find('+')
jpayne@68:         if i == -1:
jpayne@68:             i = s.find('-')
jpayne@68:         if i > 0:
jpayne@68:             data[3:] = [s[:i], s[i:]]
jpayne@68:         else:
jpayne@68:             data.append('') # Dummy tz
jpayne@68:     if len(data) < 5:
jpayne@68:         return None
jpayne@68:     data = data[:5]
jpayne@68:     [dd, mm, yy, tm, tz] = data
jpayne@68:     mm = mm.lower()
jpayne@68:     if mm not in _monthnames:
jpayne@68:         dd, mm = mm, dd.lower()
jpayne@68:         if mm not in _monthnames:
jpayne@68:             return None
jpayne@68:     mm = _monthnames.index(mm) + 1
jpayne@68:     if mm > 12:
jpayne@68:         mm -= 12
jpayne@68:     if dd[-1] == ',':
jpayne@68:         dd = dd[:-1]
jpayne@68:     i = yy.find(':')
jpayne@68:     if i > 0:
jpayne@68:         yy, tm = tm, yy
jpayne@68:     if yy[-1] == ',':
jpayne@68:         yy = yy[:-1]
jpayne@68:     if not yy[0].isdigit():
jpayne@68:         yy, tz = tz, yy
jpayne@68:     if tm[-1] == ',':
jpayne@68:         tm = tm[:-1]
jpayne@68:     tm = tm.split(':')
jpayne@68:     if len(tm) == 2:
jpayne@68:         [thh, tmm] = tm
jpayne@68:         tss = '0'
jpayne@68:     elif len(tm) == 3:
jpayne@68:         [thh, tmm, tss] = tm
jpayne@68:     elif len(tm) == 1 and '.' in tm[0]:
jpayne@68:         # Some non-compliant MUAs use '.' to separate time elements.
jpayne@68:         tm = tm[0].split('.')
jpayne@68:         if len(tm) == 2:
jpayne@68:             [thh, tmm] = tm
jpayne@68:             tss = 0
jpayne@68:         elif len(tm) == 3:
jpayne@68:             [thh, tmm, tss] = tm
jpayne@68:     else:
jpayne@68:         return None
jpayne@68:     try:
jpayne@68:         yy = int(yy)
jpayne@68:         dd = int(dd)
jpayne@68:         thh = int(thh)
jpayne@68:         tmm = int(tmm)
jpayne@68:         tss = int(tss)
jpayne@68:     except ValueError:
jpayne@68:         return None
jpayne@68:     # Check for a yy specified in two-digit format, then convert it to the
jpayne@68:     # appropriate four-digit format, according to the POSIX standard. RFC 822
jpayne@68:     # calls for a two-digit yy, but RFC 2822 (which obsoletes RFC 822)
jpayne@68:     # mandates a 4-digit yy. For more information, see the documentation for
jpayne@68:     # the time module.
jpayne@68:     if yy < 100:
jpayne@68:         # The year is between 1969 and 1999 (inclusive).
jpayne@68:         if yy > 68:
jpayne@68:             yy += 1900
jpayne@68:         # The year is between 2000 and 2068 (inclusive).
jpayne@68:         else:
jpayne@68:             yy += 2000
jpayne@68:     tzoffset = None
jpayne@68:     tz = tz.upper()
jpayne@68:     if tz in _timezones:
jpayne@68:         tzoffset = _timezones[tz]
jpayne@68:     else:
jpayne@68:         try:
jpayne@68:             tzoffset = int(tz)
jpayne@68:         except ValueError:
jpayne@68:             pass
jpayne@68:         if tzoffset==0 and tz.startswith('-'):
jpayne@68:             tzoffset = None
jpayne@68:     # Convert a timezone offset into seconds ; -0500 -> -18000
jpayne@68:     if tzoffset:
jpayne@68:         if tzoffset < 0:
jpayne@68:             tzsign = -1
jpayne@68:             tzoffset = -tzoffset
jpayne@68:         else:
jpayne@68:             tzsign = 1
jpayne@68:         tzoffset = tzsign * ( (tzoffset//100)*3600 + (tzoffset % 100)*60)
jpayne@68:     # Daylight Saving Time flag is set to -1, since DST is unknown.
jpayne@68:     return [yy, mm, dd, thh, tmm, tss, 0, 1, -1, tzoffset]
jpayne@68: 
jpayne@68: 
jpayne@68: def parsedate(data):
jpayne@68:     """Convert a time string to a time tuple."""
jpayne@68:     t = parsedate_tz(data)
jpayne@68:     if isinstance(t, tuple):
jpayne@68:         return t[:9]
jpayne@68:     else:
jpayne@68:         return t
jpayne@68: 
jpayne@68: 
jpayne@68: def mktime_tz(data):
jpayne@68:     """Turn a 10-tuple as returned by parsedate_tz() into a POSIX timestamp."""
jpayne@68:     if data[9] is None:
jpayne@68:         # No zone info, so localtime is better assumption than GMT
jpayne@68:         return time.mktime(data[:8] + (-1,))
jpayne@68:     else:
jpayne@68:         t = calendar.timegm(data)
jpayne@68:         return t - data[9]
jpayne@68: 
jpayne@68: 
jpayne@68: def quote(str):
jpayne@68:     """Prepare string to be used in a quoted string.
jpayne@68: 
jpayne@68:     Turns backslash and double quote characters into quoted pairs.  These
jpayne@68:     are the only characters that need to be quoted inside a quoted string.
jpayne@68:     Does not add the surrounding double quotes.
jpayne@68:     """
jpayne@68:     return str.replace('\\', '\\\\').replace('"', '\\"')
jpayne@68: 
jpayne@68: 
jpayne@68: class AddrlistClass:
jpayne@68:     """Address parser class by Ben Escoto.
jpayne@68: 
jpayne@68:     To understand what this class does, it helps to have a copy of RFC 2822 in
jpayne@68:     front of you.
jpayne@68: 
jpayne@68:     Note: this class interface is deprecated and may be removed in the future.
jpayne@68:     Use email.utils.AddressList instead.
jpayne@68:     """
jpayne@68: 
jpayne@68:     def __init__(self, field):
jpayne@68:         """Initialize a new instance.
jpayne@68: 
jpayne@68:         `field' is an unparsed address header field, containing
jpayne@68:         one or more addresses.
jpayne@68:         """
jpayne@68:         self.specials = '()<>@,:;.\"[]'
jpayne@68:         self.pos = 0
jpayne@68:         self.LWS = ' \t'
jpayne@68:         self.CR = '\r\n'
jpayne@68:         self.FWS = self.LWS + self.CR
jpayne@68:         self.atomends = self.specials + self.LWS + self.CR
jpayne@68:         # Note that RFC 2822 now specifies `.' as obs-phrase, meaning that it
jpayne@68:         # is obsolete syntax.  RFC 2822 requires that we recognize obsolete
jpayne@68:         # syntax, so allow dots in phrases.
jpayne@68:         self.phraseends = self.atomends.replace('.', '')
jpayne@68:         self.field = field
jpayne@68:         self.commentlist = []
jpayne@68: 
jpayne@68:     def gotonext(self):
jpayne@68:         """Skip white space and extract comments."""
jpayne@68:         wslist = []
jpayne@68:         while self.pos < len(self.field):
jpayne@68:             if self.field[self.pos] in self.LWS + '\n\r':
jpayne@68:                 if self.field[self.pos] not in '\n\r':
jpayne@68:                     wslist.append(self.field[self.pos])
jpayne@68:                 self.pos += 1
jpayne@68:             elif self.field[self.pos] == '(':
jpayne@68:                 self.commentlist.append(self.getcomment())
jpayne@68:             else:
jpayne@68:                 break
jpayne@68:         return EMPTYSTRING.join(wslist)
jpayne@68: 
jpayne@68:     def getaddrlist(self):
jpayne@68:         """Parse all addresses.
jpayne@68: 
jpayne@68:         Returns a list containing all of the addresses.
jpayne@68:         """
jpayne@68:         result = []
jpayne@68:         while self.pos < len(self.field):
jpayne@68:             ad = self.getaddress()
jpayne@68:             if ad:
jpayne@68:                 result += ad
jpayne@68:             else:
jpayne@68:                 result.append(('', ''))
jpayne@68:         return result
jpayne@68: 
jpayne@68:     def getaddress(self):
jpayne@68:         """Parse the next address."""
jpayne@68:         self.commentlist = []
jpayne@68:         self.gotonext()
jpayne@68: 
jpayne@68:         oldpos = self.pos
jpayne@68:         oldcl = self.commentlist
jpayne@68:         plist = self.getphraselist()
jpayne@68: 
jpayne@68:         self.gotonext()
jpayne@68:         returnlist = []
jpayne@68: 
jpayne@68:         if self.pos >= len(self.field):
jpayne@68:             # Bad email address technically, no domain.
jpayne@68:             if plist:
jpayne@68:                 returnlist = [(SPACE.join(self.commentlist), plist[0])]
jpayne@68: 
jpayne@68:         elif self.field[self.pos] in '.@':
jpayne@68:             # email address is just an addrspec
jpayne@68:             # this isn't very efficient since we start over
jpayne@68:             self.pos = oldpos
jpayne@68:             self.commentlist = oldcl
jpayne@68:             addrspec = self.getaddrspec()
jpayne@68:             returnlist = [(SPACE.join(self.commentlist), addrspec)]
jpayne@68: 
jpayne@68:         elif self.field[self.pos] == ':':
jpayne@68:             # address is a group
jpayne@68:             returnlist = []
jpayne@68: 
jpayne@68:             fieldlen = len(self.field)
jpayne@68:             self.pos += 1
jpayne@68:             while self.pos < len(self.field):
jpayne@68:                 self.gotonext()
jpayne@68:                 if self.pos < fieldlen and self.field[self.pos] == ';':
jpayne@68:                     self.pos += 1
jpayne@68:                     break
jpayne@68:                 returnlist = returnlist + self.getaddress()
jpayne@68: 
jpayne@68:         elif self.field[self.pos] == '<':
jpayne@68:             # Address is a phrase then a route addr
jpayne@68:             routeaddr = self.getrouteaddr()
jpayne@68: 
jpayne@68:             if self.commentlist:
jpayne@68:                 returnlist = [(SPACE.join(plist) + ' (' +
jpayne@68:                                ' '.join(self.commentlist) + ')', routeaddr)]
jpayne@68:             else:
jpayne@68:                 returnlist = [(SPACE.join(plist), routeaddr)]
jpayne@68: 
jpayne@68:         else:
jpayne@68:             if plist:
jpayne@68:                 returnlist = [(SPACE.join(self.commentlist), plist[0])]
jpayne@68:             elif self.field[self.pos] in self.specials:
jpayne@68:                 self.pos += 1
jpayne@68: 
jpayne@68:         self.gotonext()
jpayne@68:         if self.pos < len(self.field) and self.field[self.pos] == ',':
jpayne@68:             self.pos += 1
jpayne@68:         return returnlist
jpayne@68: 
jpayne@68:     def getrouteaddr(self):
jpayne@68:         """Parse a route address (Return-path value).
jpayne@68: 
jpayne@68:         This method just skips all the route stuff and returns the addrspec.
jpayne@68:         """
jpayne@68:         if self.field[self.pos] != '<':
jpayne@68:             return
jpayne@68: 
jpayne@68:         expectroute = False
jpayne@68:         self.pos += 1
jpayne@68:         self.gotonext()
jpayne@68:         adlist = ''
jpayne@68:         while self.pos < len(self.field):
jpayne@68:             if expectroute:
jpayne@68:                 self.getdomain()
jpayne@68:                 expectroute = False
jpayne@68:             elif self.field[self.pos] == '>':
jpayne@68:                 self.pos += 1
jpayne@68:                 break
jpayne@68:             elif self.field[self.pos] == '@':
jpayne@68:                 self.pos += 1
jpayne@68:                 expectroute = True
jpayne@68:             elif self.field[self.pos] == ':':
jpayne@68:                 self.pos += 1
jpayne@68:             else:
jpayne@68:                 adlist = self.getaddrspec()
jpayne@68:                 self.pos += 1
jpayne@68:                 break
jpayne@68:             self.gotonext()
jpayne@68: 
jpayne@68:         return adlist
jpayne@68: 
jpayne@68:     def getaddrspec(self):
jpayne@68:         """Parse an RFC 2822 addr-spec."""
jpayne@68:         aslist = []
jpayne@68: 
jpayne@68:         self.gotonext()
jpayne@68:         while self.pos < len(self.field):
jpayne@68:             preserve_ws = True
jpayne@68:             if self.field[self.pos] == '.':
jpayne@68:                 if aslist and not aslist[-1].strip():
jpayne@68:                     aslist.pop()
jpayne@68:                 aslist.append('.')
jpayne@68:                 self.pos += 1
jpayne@68:                 preserve_ws = False
jpayne@68:             elif self.field[self.pos] == '"':
jpayne@68:                 aslist.append('"%s"' % quote(self.getquote()))
jpayne@68:             elif self.field[self.pos] in self.atomends:
jpayne@68:                 if aslist and not aslist[-1].strip():
jpayne@68:                     aslist.pop()
jpayne@68:                 break
jpayne@68:             else:
jpayne@68:                 aslist.append(self.getatom())
jpayne@68:             ws = self.gotonext()
jpayne@68:             if preserve_ws and ws:
jpayne@68:                 aslist.append(ws)
jpayne@68: 
jpayne@68:         if self.pos >= len(self.field) or self.field[self.pos] != '@':
jpayne@68:             return EMPTYSTRING.join(aslist)
jpayne@68: 
jpayne@68:         aslist.append('@')
jpayne@68:         self.pos += 1
jpayne@68:         self.gotonext()
jpayne@68:         domain = self.getdomain()
jpayne@68:         if not domain:
jpayne@68:             # Invalid domain, return an empty address instead of returning a
jpayne@68:             # local part to denote failed parsing.
jpayne@68:             return EMPTYSTRING
jpayne@68:         return EMPTYSTRING.join(aslist) + domain
jpayne@68: 
jpayne@68:     def getdomain(self):
jpayne@68:         """Get the complete domain name from an address."""
jpayne@68:         sdlist = []
jpayne@68:         while self.pos < len(self.field):
jpayne@68:             if self.field[self.pos] in self.LWS:
jpayne@68:                 self.pos += 1
jpayne@68:             elif self.field[self.pos] == '(':
jpayne@68:                 self.commentlist.append(self.getcomment())
jpayne@68:             elif self.field[self.pos] == '[':
jpayne@68:                 sdlist.append(self.getdomainliteral())
jpayne@68:             elif self.field[self.pos] == '.':
jpayne@68:                 self.pos += 1
jpayne@68:                 sdlist.append('.')
jpayne@68:             elif self.field[self.pos] == '@':
jpayne@68:                 # bpo-34155: Don't parse domains with two `@` like
jpayne@68:                 # `a@malicious.org@important.com`.
jpayne@68:                 return EMPTYSTRING
jpayne@68:             elif self.field[self.pos] in self.atomends:
jpayne@68:                 break
jpayne@68:             else:
jpayne@68:                 sdlist.append(self.getatom())
jpayne@68:         return EMPTYSTRING.join(sdlist)
jpayne@68: 
jpayne@68:     def getdelimited(self, beginchar, endchars, allowcomments=True):
jpayne@68:         """Parse a header fragment delimited by special characters.
jpayne@68: 
jpayne@68:         `beginchar' is the start character for the fragment.
jpayne@68:         If self is not looking at an instance of `beginchar' then
jpayne@68:         getdelimited returns the empty string.
jpayne@68: 
jpayne@68:         `endchars' is a sequence of allowable end-delimiting characters.
jpayne@68:         Parsing stops when one of these is encountered.
jpayne@68: 
jpayne@68:         If `allowcomments' is non-zero, embedded RFC 2822 comments are allowed
jpayne@68:         within the parsed fragment.
jpayne@68:         """
jpayne@68:         if self.field[self.pos] != beginchar:
jpayne@68:             return ''
jpayne@68: 
jpayne@68:         slist = ['']
jpayne@68:         quote = False
jpayne@68:         self.pos += 1
jpayne@68:         while self.pos < len(self.field):
jpayne@68:             if quote:
jpayne@68:                 slist.append(self.field[self.pos])
jpayne@68:                 quote = False
jpayne@68:             elif self.field[self.pos] in endchars:
jpayne@68:                 self.pos += 1
jpayne@68:                 break
jpayne@68:             elif allowcomments and self.field[self.pos] == '(':
jpayne@68:                 slist.append(self.getcomment())
jpayne@68:                 continue        # have already advanced pos from getcomment
jpayne@68:             elif self.field[self.pos] == '\\':
jpayne@68:                 quote = True
jpayne@68:             else:
jpayne@68:                 slist.append(self.field[self.pos])
jpayne@68:             self.pos += 1
jpayne@68: 
jpayne@68:         return EMPTYSTRING.join(slist)
jpayne@68: 
jpayne@68:     def getquote(self):
jpayne@68:         """Get a quote-delimited fragment from self's field."""
jpayne@68:         return self.getdelimited('"', '"\r', False)
jpayne@68: 
jpayne@68:     def getcomment(self):
jpayne@68:         """Get a parenthesis-delimited fragment from self's field."""
jpayne@68:         return self.getdelimited('(', ')\r', True)
jpayne@68: 
jpayne@68:     def getdomainliteral(self):
jpayne@68:         """Parse an RFC 2822 domain-literal."""
jpayne@68:         return '[%s]' % self.getdelimited('[', ']\r', False)
jpayne@68: 
jpayne@68:     def getatom(self, atomends=None):
jpayne@68:         """Parse an RFC 2822 atom.
jpayne@68: 
jpayne@68:         Optional atomends specifies a different set of end token delimiters
jpayne@68:         (the default is to use self.atomends).  This is used e.g. in
jpayne@68:         getphraselist() since phrase endings must not include the `.' (which
jpayne@68:         is legal in phrases)."""
jpayne@68:         atomlist = ['']
jpayne@68:         if atomends is None:
jpayne@68:             atomends = self.atomends
jpayne@68: 
jpayne@68:         while self.pos < len(self.field):
jpayne@68:             if self.field[self.pos] in atomends:
jpayne@68:                 break
jpayne@68:             else:
jpayne@68:                 atomlist.append(self.field[self.pos])
jpayne@68:             self.pos += 1
jpayne@68: 
jpayne@68:         return EMPTYSTRING.join(atomlist)
jpayne@68: 
jpayne@68:     def getphraselist(self):
jpayne@68:         """Parse a sequence of RFC 2822 phrases.
jpayne@68: 
jpayne@68:         A phrase is a sequence of words, which are in turn either RFC 2822
jpayne@68:         atoms or quoted-strings.  Phrases are canonicalized by squeezing all
jpayne@68:         runs of continuous whitespace into one space.
jpayne@68:         """
jpayne@68:         plist = []
jpayne@68: 
jpayne@68:         while self.pos < len(self.field):
jpayne@68:             if self.field[self.pos] in self.FWS:
jpayne@68:                 self.pos += 1
jpayne@68:             elif self.field[self.pos] == '"':
jpayne@68:                 plist.append(self.getquote())
jpayne@68:             elif self.field[self.pos] == '(':
jpayne@68:                 self.commentlist.append(self.getcomment())
jpayne@68:             elif self.field[self.pos] in self.phraseends:
jpayne@68:                 break
jpayne@68:             else:
jpayne@68:                 plist.append(self.getatom(self.phraseends))
jpayne@68: 
jpayne@68:         return plist
jpayne@68: 
jpayne@68: class AddressList(AddrlistClass):
jpayne@68:     """An AddressList encapsulates a list of parsed RFC 2822 addresses."""
jpayne@68:     def __init__(self, field):
jpayne@68:         AddrlistClass.__init__(self, field)
jpayne@68:         if field:
jpayne@68:             self.addresslist = self.getaddrlist()
jpayne@68:         else:
jpayne@68:             self.addresslist = []
jpayne@68: 
jpayne@68:     def __len__(self):
jpayne@68:         return len(self.addresslist)
jpayne@68: 
jpayne@68:     def __add__(self, other):
jpayne@68:         # Set union
jpayne@68:         newaddr = AddressList(None)
jpayne@68:         newaddr.addresslist = self.addresslist[:]
jpayne@68:         for x in other.addresslist:
jpayne@68:             if not x in self.addresslist:
jpayne@68:                 newaddr.addresslist.append(x)
jpayne@68:         return newaddr
jpayne@68: 
jpayne@68:     def __iadd__(self, other):
jpayne@68:         # Set union, in-place
jpayne@68:         for x in other.addresslist:
jpayne@68:             if not x in self.addresslist:
jpayne@68:                 self.addresslist.append(x)
jpayne@68:         return self
jpayne@68: 
jpayne@68:     def __sub__(self, other):
jpayne@68:         # Set difference
jpayne@68:         newaddr = AddressList(None)
jpayne@68:         for x in self.addresslist:
jpayne@68:             if not x in other.addresslist:
jpayne@68:                 newaddr.addresslist.append(x)
jpayne@68:         return newaddr
jpayne@68: 
jpayne@68:     def __isub__(self, other):
jpayne@68:         # Set difference, in-place
jpayne@68:         for x in other.addresslist:
jpayne@68:             if x in self.addresslist:
jpayne@68:                 self.addresslist.remove(x)
jpayne@68:         return self
jpayne@68: 
jpayne@68:     def __getitem__(self, index):
jpayne@68:         # Make indexing, slices, and 'in' work
jpayne@68:         return self.addresslist[index]