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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 nbytes(self):
 """The number of bytes required to encode this command. Encoded commands are comprised of a two byte opcode, followed by a one byte size, and then the command argument bytes. The size indicates the number of bytes required to represent command arguments. """

        return len(self.opcode) + 1 + sum(arg.nbytes for arg in self.argdefns)