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diff --git a/files/.offlineimap-utf7.py b/files/.offlineimap-utf7.py
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+# -*- coding: latin-1 -*-
+ 
+"""
+Imap folder names are encoded using a special version of utf-7 as defined in RFC 
+2060 section 5.1.3.
+ 
+5.1.3.  Mailbox International Naming Convention
+ 
+   By convention, international mailbox names are specified using a
+   modified version of the UTF-7 encoding described in [UTF-7].  The
+   purpose of these modifications is to correct the following problems
+   with UTF-7:
+ 
+      1) UTF-7 uses the "+" character for shifting; this conflicts with
+         the common use of "+" in mailbox names, in particular USENET
+         newsgroup names.
+ 
+      2) UTF-7's encoding is BASE64 which uses the "/" character; this
+         conflicts with the use of "/" as a popular hierarchy delimiter.
+ 
+      3) UTF-7 prohibits the unencoded usage of "\"; this conflicts with
+         the use of "\" as a popular hierarchy delimiter.
+ 
+      4) UTF-7 prohibits the unencoded usage of "~"; this conflicts with
+         the use of "~" in some servers as a home directory indicator.
+ 
+      5) UTF-7 permits multiple alternate forms to represent the same
+         string; in particular, printable US-ASCII chararacters can be
+         represented in encoded form.
+ 
+   In modified UTF-7, printable US-ASCII characters except for "&"
+   represent themselves; that is, characters with octet values 0x20-0x25
+   and 0x27-0x7e.  The character "&" (0x26) is represented by the two-
+   octet sequence "&-".
+ 
+   All other characters (octet values 0x00-0x1f, 0x7f-0xff, and all
+   Unicode 16-bit octets) are represented in modified BASE64, with a
+   further modification from [UTF-7] that "," is used instead of "/".
+   Modified BASE64 MUST NOT be used to represent any printing US-ASCII
+   character which can represent itself.
+ 
+   "&" is used to shift to modified BASE64 and "-" to shift back to US-
+   ASCII.  All names start in US-ASCII, and MUST end in US-ASCII (that
+   is, a name that ends with a Unicode 16-bit octet MUST end with a "-
+   ").
+ 
+      For example, here is a mailbox name which mixes English, Japanese,
+      and Chinese text: ~peter/mail/&ZeVnLIqe-/&U,BTFw-
+ 
+"""
+import binascii
+import codecs
+ 
+# encoding
+ 
+def modified_base64(s):
+    s = s.encode('utf-16be')
+    return binascii.b2a_base64(s).rstrip('\n=').replace('/', ',')
+ 
+def doB64(_in, r):
+    if _in:
+        r.append('&%s-' % modified_base64(''.join(_in)))
+        del _in[:]
+ 
+def encoder(s):
+    r = []
+    _in = []
+    for c in s:
+        ordC = ord(c)
+        if 0x20 <= ordC <= 0x25 or 0x27 <= ordC <= 0x7e:
+            doB64(_in, r)
+            r.append(c)
+        elif c == '&':
+            doB64(_in, r)
+            r.append('&-')
+        else:
+            _in.append(c)
+    doB64(_in, r)
+    return (str(''.join(r)), len(s))
+ 
+ 
+# decoding
+ 
+def modified_unbase64(s):
+    b = binascii.a2b_base64(s.replace(',', '/') + '===')
+    return unicode(b, 'utf-16be')
+ 
+ 
+def decoder(s):
+    r = []
+    decode = []
+    for c in s:
+        if c == '&' and not decode:
+            decode.append('&')
+        elif c == '-' and decode:
+            if len(decode) == 1:
+                r.append('&')
+            else:
+                r.append(modified_unbase64(''.join(decode[1:])))
+            decode = []
+        elif decode:
+            decode.append(c)
+        else:
+            r.append(c)
+    if decode:
+        r.append(modified_unbase64(''.join(decode[1:])))
+    bin_str = ''.join(r)
+    return (bin_str, len(s))
+ 
+ 
+class StreamReader(codecs.StreamReader):
+    def decode(self, s, errors='strict'):
+        return decoder(s)
+ 
+ 
+class StreamWriter(codecs.StreamWriter):
+    def decode(self, s, errors='strict'):
+        return encoder(s)
+ 
+ 
+def imap4_utf_7(name):
+    if name == 'imap4-utf-7':
+        return (encoder, decoder, StreamReader, StreamWriter)
+codecs.register(imap4_utf_7)