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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 dns_get_str(s, pointer=0, pkt=None, _fullpacket=False):
 """This function decompresses a string s, starting from the given pointer. :param s: the string to decompress :param pointer: first pointer on the string (default: 0) :param pkt: (optional) an InheritOriginDNSStrPacket packet :returns: (decoded_string, end_index, left_string) """

    # The _fullpacket parameter is reserved for scapy. It indicates
    # that the string provided is the full dns packet, and thus
    # will be the same than pkt._orig_str. The "Cannot decompress"
    # error will not be prompted if True.
    max_length = len(s)
    # The result = the extracted name
    name = b""
    # Will contain the index after the pointer, to be returned
    after_pointer = None
    processed_pointers = []  # Used to check for decompression loops
    # Analyse given pkt
    if pkt and hasattr(pkt, "_orig_s") and pkt._orig_s:
        s_full = pkt._orig_s
    else:
        s_full = None
    bytes_left = None
    while True:
        if abs(pointer) >= max_length:
            warning("DNS RR prematured end (ofs=%i, len=%i)" % (pointer,
                                                                len(s)))
            break
        cur = orb(s[pointer])  # get pointer value
        pointer += 1  # make pointer go forward
        if cur & 0xc0:  # Label pointer
            if after_pointer is None:
                # after_pointer points to where the remaining bytes start,
                # as pointer will follow the jump token
                after_pointer = pointer + 1
            if pointer >= max_length:
                warning("DNS incomplete jump token at (ofs=%i)" % pointer)
                break
            # Follow the pointer
            pointer = ((cur & ~0xc0) << 8) + orb(s[pointer]) - 12
            if pointer in processed_pointers:
                warning("DNS decompression loop detected")
                break
            if not _fullpacket:
                # Do we have access to the whole packet ?
                if s_full:
                    # Yes -> use it to continue
                    bytes_left = s[after_pointer:]
                    s = s_full
                    max_length = len(s)
                    _fullpacket = True
                else:
                    # No -> abort
                    raise Scapy_Exception("DNS message can't be compressed" +
                                          "at this point!")
            processed_pointers.append(pointer)
            continue
        elif cur > 0:  # Label
            # cur = length of the string
            name += s[pointer:pointer + cur] + b"."
            pointer += cur
        else:
            break
    if after_pointer is not None:
        # Return the real end index (not the one we followed)
        pointer = after_pointer
    if bytes_left is None:
        bytes_left = s[pointer:]
    # name, end_index, remaining
    return name, pointer, bytes_left