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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 init_group_write(self, dst_addr=1, data=None, dptsize=0):
 """Initialize the CEMI frame for a group write operation."""

        self.init_group(dst_addr)

        # unnumbered data packet, group write
        self.tpci_apci = 0x00 * 256 + 0x80

        self.dptsize = dptsize
        if data is None:
            self.data = [0]
        else:
            self.data = data