Thanks Gordon,
So I now have double quotes back in and I have tested the connection and it has worked ok so far in terms of not giving the connection error.However the console output looks werid and the watch display is blank.
So I will post the complete code.

``
#!/usr/bin/env python3

import asyncio
import array
from bleak import discover
from bleak import BleakClient
import json

#create dictionary for the data to be sent
dict = {'Code': '10'}

address = "D8:AB:E0:B7:F5:AE"
UUID_NORDIC_TX = "6e400002-b5a3-f393-e0a9-e50e24dcca9e"
UUID_NORDIC_RX = "6e400003-b5a3-f393-e0a9-e50e24dcca9e"
#command = "X("+json.dumps(dict)+")\n"
#command = b"E.showMessage('Hello','A Title')/n"
command = "Y("+json.dumps(dict)+")\n"

def uart_data_received(sender, data):

print("RX> {0}".format(data))

You can scan for devices with:

async def run():

devices = await discover()
for d in devices:
    print(d)

print("Connecting...")
async def run(address, loop):

async with BleakClient(address, loop=loop) as client:
    print("Connected")
    await client.start_notify(UUID_NORDIC_RX, uart_data_received)
    print("Writing command")
    c=command
    while len(c)>0:
      await client.write_gatt_char(UUID_NORDIC_TX,bytearray((c[0:20]),'utf-8') , True)
      c = c[20:]
    print("Waiting for data")
    await asyncio.sleep(1.0, loop=loop) # wait for a response
    print("Done!")

loop = asyncio.get_event_loop()
loop.run_until_complete(run(address, loop))

My app. Note function is now Y.

E.showMessage("Hello Code");

function Y(dict) {
E.showMessage(dict);

}

and the console

Connecting...
Connected
Writing command
Waiting for data
RX> bytearray(b'Y({"Code": "10"})\r\n')
RX> bytearray(b'Y({"Code": "10"})\r\n')
RX> bytearray(b'Uncaught Error: Func')
RX> bytearray(b'Uncaught Error: Func')
RX> bytearray(b'tion "split" not fou')
RX> bytearray(b'tion "split" not fou')
RX> bytearray(b'nd!\r\n at line 1 col ')
RX> bytearray(b'nd!\r\n at line 1 col ')
RX> bytearray(b'250\r\n...ect(c/2-b,44')
RX> bytearray(b'250\r\n...ect(c/2-b,44')
RX> bytearray(b',c/2+b,45)}b=e.split')
RX> bytearray(b',c/2+b,45)}b=e.split')
RX> bytearray(b'("\n");var h=(f-16*b')
RX> bytearray(b'("\n");var h=(f-16*b')
RX> bytearray(b'.length)...\r\n ')
RX> bytearray(b'.length)...\r\n ')
RX> bytearray(b' ')
RX> bytearray(b' ')
RX> bytearray(b' ^\r\nin function ca')
RX> bytearray(b' ^\r\nin function ca')
RX> bytearray(b'lled from line 1 col')
RX> bytearray(b'lled from line 1 col')
RX> bytearray(b' 19\r\nE.showMessage(d')
RX> bytearray(b' 19\r\nE.showMessage(d')
RX> bytearray(b'ict);\r\n ')
RX> bytearray(b'ict);\r\n ')
RX> bytearray(b' ^\r\nat line 1 co')
RX> bytearray(b' ^\r\nat line 1 co')
RX> bytearray(b'l 19\r\nE.showMessage(')
RX> bytearray(b'l 19\r\nE.showMessage(')
RX> bytearray(b'dict);\r\n ')
RX> bytearray(b'dict);\r\n ')
RX> bytearray(b' ^\r\nin function')
RX> bytearray(b' ^\r\nin function')
RX> bytearray(b' "Y" called from lin')
RX> bytearray(b' "Y" called from lin')
RX> bytearray(b'e 1 col 17\r\nY({"Code')
RX> bytearray(b'e 1 col 17\r\nY({"Code')
RX> bytearray(b'": "10"})\r\n ')
RX> bytearray(b'": "10"})\r\n ')
RX> bytearray(b' ^\r\n>')
RX> bytearray(b' ^\r\n>')
Done!

```
Any help most appreciated.