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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 decode_options(self, buffer):
 """This method decodes the section of the buffer that contains an unknown number of options. It returns a dictionary of option names and values."""

        fmt = b"!"
        options = {}

        log.debug("decode_options: buffer is: %s", repr(buffer))
        log.debug("size of buffer is %d bytes", len(buffer))
        if len(buffer) == 0:
            log.debug("size of buffer is zero, returning empty hash")
            return {}

        # Count the nulls in the buffer. Each one terminates a string.
        log.debug("about to iterate options buffer counting nulls")
        length = 0
        for i in range(len(buffer)):
            if ord(buffer[i:i+1]) == 0:
                log.debug("found a null at length %d", length)
                if length > 0:
                    fmt += b"%dsx" % length
                    length = -1
                else:
                    raise TftpException("Invalid options in buffer")
            length += 1

        log.debug("about to unpack, fmt is: %s", fmt)
        mystruct = struct.unpack(fmt, buffer)

        tftpassert(len(mystruct) % 2 == 0,
                   "packet with odd number of option/value pairs")

        for i in range(0, len(mystruct), 2):
            key = mystruct[i].decode('ascii')
            val = mystruct[i+1].decode('ascii')
            log.debug("setting option %s to %s", key, val)
            log.debug("types are %s and %s", type(key), type(val))
            options[key] = val

        return options