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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 standard_block(self, _bytes):
 """ Adds a standard block of bytes """

        self.out(self.BLOCK_STANDARD)  # Standard block ID
        self.out(self.LH(1000))  # 1000 ms standard pause
        self.out(self.LH(len(_bytes) + 1))  # + 1 for CHECKSUM byte

        checksum = 0
        for i in _bytes:
            checksum ^= (int(i) & 0xFF)
            self.out(i)

        self.out(checksum)