How to use flow control in pyserial

Question

I need help is using serial port, I have 3DR radio telemetry connected to my python and other side to my windows PC ,I have small python code which continiously writes the data to serial port and reads , reading might not be an issue, or it might be later anyway...

The issue is i am afraid the too many writes might cause some buffer overflow, every time i search the solution is to enable rts/cts flow control, I dont know how to use it ?? what will happen if i set these then pyserial will do what and how can i control my write ?? its really confusing ..

hardware flow ccontol, I am not sure it might work, becuase I have just connected rx tx ground and power to my raspberry pi, even if try to connect the other flow control pins to pi, i am not sure it works or supported by 3dr radio telemetry.. I believe software flow control will be good and simple solution for now.

here is my code ..

for channel in list(self.__channelDict.values()):

            # Addition for channel priority later
            # We check if the channels in the list is active
            if channel.getChannelActive() is True:
                # Check if we have reached the max count
                if (messageCount >= (self.__NoOfMessagesInUARTStream - 1)) or UARTForceSend:
                    self.sendUARTStream(UARTCacheBuffer, messageCount, UARTStreamCRC)
                    # Reset
                    messageCount  = 0
                    UARTStreamCRC = 0
                    UARTCacheBuffer.emptyBuffer()

                message = channel.RetriveMessage(queueType = 1, raw = True)
                # # there is no TX message in this channel
                if message is None:
                    continue # continue with next channel
                else:
                    UARTStreamCRC = binascii.crc32(message, UARTStreamCRC)
                    UARTCacheBuffer.append(message, raw = True)
                    messageCount +=1

and the function to write to serial port

def sendUARTStream(self, UARTCacheBuffer, messageCount, UARTStreamCRC):
    # retrieve all the data from the buffer and create a stream packet
    UARTFrame        = None       # Used to forward the data
    UARTStreamHeader = None

    # Create the message header
    if messageCount == 0:
        # looks like all channels are empty 
        return 0
    else:
        messageArray     = UARTCacheBuffer.getBuffer()
        print(messageArray)
        print('messageCount = ' + str(messageCount) +  'crc = ' + str(UARTStreamCRC))

        UARTFrame[:self.__UARTStreamHeaderFormat.size] = self.createHeader(messageCount, UARTStreamCRC)
        UARTFrame[self.__UARTStreamHeaderFormat.size : self.__UARTStreamHeaderFormat.size + self.__messageFormat * messageCount] =  messageArray
        # Its time to finally send the data
        print('UARTFrame  = ##' + str(UARTFrame))
        self.__txPort.write(UARTFrame)
    return messageCount