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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(self):
 """Decompress compressed UTF16 value."""

        hi = self.enc_byte()
        flagbits = 0
        while self.encpos < len(self.encdata):
            if flagbits == 0:
                flags = self.enc_byte()
                flagbits = 8
            flagbits -= 2
            t = (flags >> flagbits) & 3
            if t == 0:
                self.put(self.enc_byte(), 0)
            elif t == 1:
                self.put(self.enc_byte(), hi)
            elif t == 2:
                self.put(self.enc_byte(), self.enc_byte())
            else:
                n = self.enc_byte()
                if n & 0x80:
                    c = self.enc_byte()
                    for _ in range((n & 0x7f) + 2):
                        lo = (self.std_byte() + c) & 0xFF
                        self.put(lo, hi)
                else:
                    for _ in range(n + 2):
                        self.put(self.std_byte(), 0)
        return self.buf.decode("utf-16le", "replace")