1) You can only pass JSON data and not a list/array in the request. You can pass the data like this:

some_data = {'data': [
    {
        "A": "John",
        "B": 1000
    },
    {
        "A": "Jane",
        "B": 500
    }
]}

2) Your Odoo route should have authentication "public/none":
auth='none' or auth='public'

@http.route('/odoo_api_ep', type='json', auth='none')

Modify your code as per the suggestion and it will work.

SCRIPT:

import json
import requests
ODOO_ENDPOINT = "http://0.0.0.0:8069/odoo_api_ep"
API_HEADERS = {'Content-type': 'application/json', 'Accept': 'text/plain'}
some_data = {'data': [
    {
        "A": "John",
        "B": 1000
    },
    {
        "A": "Jane",
        "B": 500
    }
]}
some_data = json.dumps(some_data)
r = requests.get(ODOO_ENDPOINT, headers=API_HEADERS, data=some_data)
print("rrrr... ", r.text)

Odoo Route:

@http.route('/odoo_api_ep', type='json', auth='none')
def incoming_data_api(self, context=None):
    my_data = request.jsonrequest
    print("\n\nmy_data.....    ", my_data)
    return my_data