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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 trace_set_buffer_capacity(self, size):
 """Sets the capacity for the trace buffer. Args: self (JLink):
 the ``JLink`` instance. size (int):
 the new capacity for the trace buffer. Returns: ``None`` """

        cmd = enums.JLinkTraceCommand.SET_CAPACITY
        data = ctypes.c_uint32(size)
        res = self._dll.JLINKARM_TRACE_Control(cmd, ctypes.byref(data))
        if (res == 1):
            raise errors.JLinkException('Failed to set trace buffer size.')
        return None