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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 decrypt(self, block):
 """Decrypt blocks."""


        if len(block) % 16:
            raise ValueError("block size must be a multiple of 16")

        plaintext = b''

        while block:
            a, b, c, d = struct.unpack("<4L", block[:16])
            temp = [a, b, c, d]
            decrypt(self.context, temp)
            plaintext += struct.pack("<4L", *temp)
            block = block[16:]

        return plaintext