coinex exchange API and use Curl /BASH to Place a market order crypto pair

I am trying to place a market order in the www.coinex.com crypto exchange, by application of the curl in the BASH environment. I use following official guidelines:
API Invocation Instruction
Place Market Order

My code reads inputs (amount, price, market, type,…), generates sign-in data by MD5 algorithm, and sends POST by curl.
CODE:

    #!/bin/bash
    #A code to put a market order in the www.coinex.com exchange pairs 

    #My Access ID in www.coinex.com  
    access_id="XXXX" 
    #My secrect Key  in www.coinex.com  
    secret_key="XXXX"  
    #Request Url 
    get_url="https://api.coinex.com/v1/order/market" 
    #Any Amount 
    amount="1.0"  
    #Any pair in the Market
    marketpair="DOGEUSDT"  
    #buy or sell
    market_type="sell" 
    #the market price 
    price="0.041" 
    #Get servertime, Tonce is a timestamp with a positive Interger that represents the number of milliseconds from Unix epoch to the current time. Error between tonce and server time can not exceed plus or minus 60s
    tonce=`curl -X GET  https://api.coinex.com/v1/market/ticker/all |  jq .data.date`

    #authorization code using 32-bit MD5 Algorithm Signature
    authorization=`echo -n  'access_id='$access_id'&amount='$amount'&market='$marketpair'&price='$price'&tonce='$tonce'&type='$market_type'&secret_key='$secret_key''|md5sum`

    #Convert authorization to UPPERCASE
    echo ${authorization^^}

    #Place market order 
    curl   -v  -H  "authorization:'$authorization'"  -H   "Content-Type: application/json" -X -POST    -d  '{"access_id":"'$access_id'", "amount": "'$amount'","market":"'$market'","price": "'$price'",  "tonce": "'$tonce'",       "type": "'$market_type'"}'      $get_url

ERROR:

    <html>
    <head><title>400 Bad Request</title></head>
    <body bgcolor="white">
    <center><h1>400 Bad Request</h1></center>
    <hr><center>nginx</center>
    </body>
    </html>
    * Connection #0 to host 127.0.0.1 left intact

Also, I use a VPN for the internet.

Solution

I succeeded to solve problem with the following package ( I run it in Google colab):

https://pythonrepo.com/repo/imanmousaei-coinexpy