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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 inet_aton(text):
 """Convert a text format IPv6 address into network format. @param text: the textual address @type text: string @rtype: string @raises dns.exception.SyntaxError: the text was not properly formatted """


    #
    # Our aim here is not something fast; we just want something that works.
    #

    if text == '::':
        text = '0::'
    #
    # Get rid of the icky dot-quad syntax if we have it.
    #
    m = _v4_ending.match(text)
    if not m is None:
        text = "%s:%04x:%04x" % (m.group(1),
                                 int(m.group(2)) * 256 + int(m.group(3)),
                                 int(m.group(4)) * 256 + int(m.group(5)))
    #
    # Try to turn '::<whatever>' into ':<whatever>'; if no match try to
    # turn '<whatever>::' into '<whatever>:'
    #
    m = _colon_colon_start.match(text)
    if not m is None:
        text = text[1:]
    else:
        m = _colon_colon_end.match(text)
        if not m is None:
            text = text[:-1]
    #
    # Now canonicalize into 8 chunks of 4 hex digits each
    #
    chunks = text.split(':')
    l = len(chunks)
    if l > 8:
        raise dns.exception.SyntaxError
    seen_empty = False
    canonical = []
    for c in chunks:
        if c == '':
            if seen_empty:
                raise dns.exception.SyntaxError
            seen_empty = True
            for i in xrange(0, 8 - l + 1):
                canonical.append('0000')
        else:
            lc = len(c)
            if lc > 4:
                raise dns.exception.SyntaxError
            if lc != 4:
                c = ('0' * (4 - lc)) + c
            canonical.append(c)
    if l < 8 and not seen_empty:
        raise dns.exception.SyntaxError
    text = ''.join(canonical)

    #
    # Finally we can go to binary.
    #
    try:
        return text.decode('hex_codec')
    except TypeError:
        raise dns.exception.SyntaxError