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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 usb_control_out(library, session, request_type_bitmap_field, request_id, request_value, index, data=""):
 """Performs a USB control pipe transfer to the device. Corresponds to viUsbControlOut function of the VISA library. :param library: the visa library wrapped by ctypes. :param session: Unique logical identifier to a session. :param request_type_bitmap_field: bmRequestType parameter of the setup stage of a USB control transfer. :param request_id: bRequest parameter of the setup stage of a USB control transfer. :param request_value: wValue parameter of the setup stage of a USB control transfer. :param index: wIndex parameter of the setup stage of a USB control transfer. This is usually the index of the interface or endpoint. :param data: The data buffer that sends the data in the optional data stage of the control transfer. :return: return value of the library call. :rtype: :class:`pyvisa.constants.StatusCode` """

    length = len(data)
    return library.viUsbControlOut(session, request_type_bitmap_field, request_id,
                                   request_value, index, length, data)