How to make a post request with the Python requests library?

Using the following filters in Postman to make a POST request in a Web API but I am unable to make a simple POST request in Python with the requests library.

First, I am sending a POST request to this URL (http://10.61.202.98:8081/T/a/api/rows/cat/ect/tickets) with the following filters in Postman applied to the Body, with the raw and JSON(application/json) options selected.

Filters in Postman

{
  "filter": {
    "filters": [
      {
        "field": "RCA_Assigned_Date",
        "operator": "gte",
        "value": "2017-05-31 00:00:00"
      },
      {
        "field": "RCA_Assigned_Date",
        "operator": "lte",
        "value": "2017-06-04 00:00:00"
      },
      {
        "field": "T_Subcategory",
        "operator": "neq",
        "value": "Temporary Degradation"
      },
      {
        "field": "Issue_Status",
        "operator": "neq",
        "value": "Queued"
      }],
     "logic": "and"
    }
}

The database where the data is stored is Cassandra and according to the following links Cassandra not equal operator, Cassandra OR operator, Cassandra Between order by operators, Cassandra does not support the NOT EQUAL TO, OR, BETWEEN operators, so there is no way I can filter the URL with these operators except with AND.

Second,  using the following code to apply a simple filter with the requests library.

import requests
payload = {'field':'T_Subcategory','operator':'neq','value':'Temporary Degradation'}
url = requests.post("http://10.61.202.98:8081/T/a/api/rows/cat/ect/tickets",data=payload)

But what I've got is the complete data of tickets instead of only those that are not temporary degradation.

Third, the system is actually working but we are experiencing a delay of 2-3 mins to see the data. The logic goes as follows: We have 8 users and we want to see all the tickets per user that are not temporary degradation, then we do:

def get_json():
    if user_name == "user 001":
        with urllib.request.urlopen(
    "http://10.61.202.98:8081/T/a/api/rows/cat/ect/tickets?user_name=user&001",timeout=15) as url:
            complete_data = json.loads(url.read().decode())

    elif user_name == "user 002":
        with urllib.request.urlopen(             
    "http://10.61.202.98:8081/T/a/api/rows/cat/ect/tickets?user_name=user&002",timeout=15) as url:
            complete_data = json.loads(url.read().decode())
    return complete_data

def get_tickets_not_temp_degradation(start_date,end_date,complete_):
    return Counter([k['user_name'] for k in complete_data if start_date < dateutil.parser.parse(k.get('DateTime')) < end_date and k['T_subcategory'] != 'Temporary Degradation'])

Basically, we get the whole set of tickets from the current and last year, then we let Python to filter the complete set by user and so far there are only 10 users which means that this process is repeated 10 times and makes me no surprise to discover why we get the delay...

How can I fix this problem of the requests library?