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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def encode(self, splitchars=';, \t', maxlinelen=None, linesep='\n'):
 r"""Encode a message header into an RFC-compliant format. There are many issues involved in converting a given string for use in an email header. Only certain character sets are readable in most email clients, and as header strings can only contain a subset of 7-bit ASCII, care must be taken to properly convert and encode (with Base64 or quoted-printable) header strings. In addition, there is a 75-character length limit on any given encoded header field, so line-wrapping must be performed, even with double-byte character sets. Optional maxlinelen specifies the maximum length of each generated line, exclusive of the linesep string. Individual lines may be longer than maxlinelen if a folding point cannot be found. The first line will be shorter by the length of the header name plus ": " if a header name was specified at Header construction time. The default value for maxlinelen is determined at header construction time. Optional splitchars is a string containing characters which should be given extra weight by the splitting algorithm during normal header wrapping. This is in very rough support of RFC 2822's `higher level syntactic breaks': split points preceded by a splitchar are preferred during line splitting, with the characters preferred in the order in which they appear in the string. Space and tab may be included in the string to indicate whether preference should be given to one over the other as a split point when other split chars do not appear in the line being split. Splitchars does not affect RFC 2047 encoded lines. Optional linesep is a string to be used to separate the lines of the value. The default value is the most useful for typical Python applications, but it can be set to \r\n to produce RFC-compliant line separators when needed. """

        self._normalize()
        if maxlinelen is None:
            maxlinelen = self._maxlinelen
        # A maxlinelen of 0 means don't wrap.  For all practical purposes,
        # choosing a huge number here accomplishes that and makes the
        # _ValueFormatter algorithm much simpler.
        if maxlinelen == 0:
            maxlinelen = 1000000
        formatter = _ValueFormatter(self._headerlen, maxlinelen,
                                    self._continuation_ws, splitchars)
        lastcs = None
        hasspace = lastspace = None
        for string, charset in self._chunks:
            if hasspace is not None:
                hasspace = string and self._nonctext(string[0])
                import sys
                if lastcs not in (None, 'us-ascii'):
                    if not hasspace or charset not in (None, 'us-ascii'):
                        formatter.add_transition()
                elif charset not in (None, 'us-ascii') and not lastspace:
                    formatter.add_transition()
            lastspace = string and self._nonctext(string[-1])
            lastcs = charset
            hasspace = False
            lines = string.splitlines()
            if lines:
                formatter.feed('', lines[0], charset)
            else:
                formatter.feed('', '', charset)
            for line in lines[1:]:
                formatter.newline()
                if charset.header_encoding is not None:
                    formatter.feed(self._continuation_ws, ' ' + line.lstrip(),
                                   charset)
                else:
                    sline = line.lstrip()
                    fws = line[:len(line)-len(sline)]
                    formatter.feed(fws, sline, charset)
            if len(lines) > 1:
                formatter.newline()
        if self._chunks:
            formatter.add_transition()
        value = formatter._str(linesep)
        if _embeded_header.search(value):
            raise HeaderParseError("header value appears to contain "
                "an embedded header: {!r}".format(value))
        return value