def encode(body, binary=False, maxlinelen=76, eol=NL):
    if not body:
        return body

    if not binary:
        body = fix_eols(body)

    # BAW: We're accumulating the body text by string concatenation.  That
    # can't be very efficient, but I don't have time now to rewrite it.  It
    # just feels like this algorithm could be more efficient.
    encoded_body = ''
    lineno = -1
    # Preserve line endings here so we can check later to see an eol needs to
    # be added to the output later.
    lines = body.splitlines(1)
    for line in lines:
        # But strip off line-endings for processing this line.
        if line.endswith(CRLF):
            line = line[:-2]
        elif line[-1] in CRLF:
            line = line[:-1]

        lineno += 1
        encoded_line = ''
        prev = None
        linelen = len(line)
        # Now we need to examine every character to see if it needs to be
        # quopri encoded.  BAW: again, string concatenation is inefficient.
        for j in range(linelen):
            c = line[j]
            prev = c
            if bqre.match(c):
                c = quote(c)
            elif j+1 == linelen:
                # Check for whitespace at end of line; special case
                if c not in ' \t':
                    encoded_line += c
                prev = c
                continue
            # Check to see to see if the line has reached its maximum length
            if len(encoded_line) + len(c) >= maxlinelen:
                encoded_body += encoded_line + '=' + eol
                encoded_line = ''
            encoded_line += c
        # Now at end of line..
        if prev and prev in ' \t':
            # Special case for whitespace at end of file
            if lineno + 1 == len(lines):
                prev = quote(prev)
                if len(encoded_line) + len(prev) > maxlinelen:
                    encoded_body += encoded_line + '=' + eol + prev
                else:
                    encoded_body += encoded_line + prev
            # Just normal whitespace at end of line
            else:
                encoded_body += encoded_line + prev + '=' + eol
            encoded_line = ''
        # Now look at the line we just finished and it has a line ending, we
        # need to add eol to the end of the line.
        if lines[lineno].endswith(CRLF) or lines[lineno][-1] in CRLF:
            encoded_body += encoded_line + eol
        else:
            encoded_body += encoded_line
        encoded_line = ''
    return encoded_body


# For convenience and backwards compatibility w/ standard base64 module
Encode with quoted-printable, wrapping at maxlinelen characters.
dataset/ETHPy150Open babble/babble/include/jython/Lib/email/quoprimime.py/encode