Using python post request instead of openai client

I want to use the batch api . But instead of the following code by creating a client , I need to use python post request .

batch_input_file = client.files.create(
  file=open("batchinput.jsonl", "rb"),
  purpose="batch"
)


batch_input_file_id = batch_input_file.id

client.batches.create(
    input_file_id=batch_input_file_id,
    endpoint="/v1/chat/completions",
    completion_window="24h",
    metadata={
      "description": "nightly eval job"
    }
)

Following is what I did , but I am getting error : {‘statusCode’: 404, ‘message’: ‘Resource not found’}

data1={
'purpose'="batch"
}

requests_list=[]
id=1

for request in bulk_requests:
       requests_list.append(
      {
      "custom_id":str(id),
     "method":POST,
     "url":"/v1/chat/completions",
     "body":{ 
         "model":model,
        "messages":request
}})
   id+=1

with open('batchinput.jsonl','w') as file:
     for request in requests_list:
           file.write(json.dumps(request)+'\n')

myfile={'file':open('batchinput.jsonl'),'rb'}
batch_input_file_response=requests.post("https://api.openai.com/v1/files",
 data=data1,files=myfile)

batch_input_file=batch_input_file_response.json
print(batch_input_file)

data2={
"input_file_id": batch_input_file.get('id'),
"completion_window":"24h"
}

batch_object_output=requests.post("https://api.openai.com/v1/batches",data=data2)
print(batch_object_output.json)