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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 set_payload_format(self, payload_format):
 """Set the payload format for messages sent to and from the VI. Returns True if the command was successful. """

        request = {
            "command": "payload_format",
            "format": payload_format
        }
        status = self._check_command_response_status(request)
        # Always change the format regardless because if it was already in the
        # right format, the command will have failed.
        self.format = payload_format
        return status