I would personally do something like this:

import json
import datetime

today = datetime.date.today()
tomorrow = today + datetime.timedelta(days = 1)

data = [{
    "date": str(tomorrow),
    "price": {
        "amount": 15100
    }
}]

print(json.dumps(data))

Of course, after this, you can do anything you want with json.dumps(data): in your case, send it in a request.

You can put extra{ and } to your string:

import json

test = 10
json_data = f'[{{"ID": {test},"Name":"Pankaj","Role":"CEO"}}]'

json_object = json.loads(json_data)
json_formatted_str = json.dumps(json_object, indent=2)
print(json_formatted_str)

Prints:

[
  {
    "ID": 10,
    "Name": "Pankaj",
    "Role": "CEO"
  }
]

you should use string.format() instead of f-strings

Still if you want to use f-strings then you should use eval like this, its unsafe

DAY="1"
MONTH="12"
df = pd.DataFrame(
    [{
    "path":"home/data/month={MONTH}/day={DAY}"
 },
 {
    "path":"home/data/month={MONTH}/day={DAY}"
 }
]
)
a = df['path'][0]
print(eval(f"f'{a}'"))
#home/data/month=12/day=1

As I suggested, just convert the nested JSON to a dict and manipulate it:

import json

payload = {
   "query": "query ($network: EthereumNetwork!, $dateFormat: String!, $from: ISO8601DateTime, $till: ISO8601DateTime) {\n  ethereum(network: $network) {\n    transactions(options: {asc: \"date.date\"}, date: {since: $from, till: $till}) {\n      date: date {\n        date(format: $dateFormat)\n      }\n      count: countBigInt\n      gasValue\n    }\n  }\n}\n",
   "variables": "{\n  \"limit\": 10,\n  \"offset\": 0,\n  \"network\": \"ethereum\",\n  \"from\": \"2022-11-25T23:59:59\",\"till\":\"2022-11-28T23:59:59\",\n  \"dateFormat\": \"%Y-%m-%d\"\n}"
}

var = json.loads(payload['variables'])
var['from'] = var['from'].replace('2022','2024')
payload['variables'] = json.dumps(var)
print(json.dumps(payload))

Output:

{"query": "query ($network: EthereumNetwork!, $dateFormat: String!, $from: ISO8601DateTime, $till: ISO8601DateTime) {\n  ethereum(network: $network) {\n    transactions(options: {asc: \"date.date\"}, date: {since: $from, till: $till}) {\n      date: date {\n        date(format: $dateFormat)\n      }\n      count: countBigInt\n      gasValue\n    }\n  }\n}\n", "variables": "{\"limit\": 10, \"offset\": 0, \"network\": \"ethereum\", \"from\": \"2024-11-25T23:59:59\", \"till\": \"2022-11-28T23:59:59\", \"dateFormat\": \"%Y-%m-%d\"}"}

You need to double the outer braces; otherwise Python thinks { "File".. is a reference too:

output_format = '{{ "File": "{filename}", "Success": {success}, "ErrorMessage": "{error_msg}", "LogIdentifier": "{log_identifier}" }}'

Result:

>>> print output_format.format(filename='My_file_name',
...                            success=True,
...                            error_msg='',
...                            log_identifier='123')
{ "File": "My_file_name", "Success": True, "ErrorMessage": "", "LogIdentifier": "123" }

If, indicentally, you are producing JSON output, you'd be better off using the json module:

>>> import json
>>> print json.dumps({'File': 'My_file_name',
...                   'Success': True,
...                   'ErrorMessage': '',
...                   'LogIdentifier': '123'})
{"LogIdentifier": "123", "ErrorMessage": "", "Success": true, "File": "My_file_name"}

Note the lowercase true in the output, as required by the JSON standard.

{} has special meaning in str.format (place holder and variable name), if you need literal {} with format, you can use {{ and }}:

TODO_JSON = '{{"id": {0},"title": {1},"completed:" {2}}}'
print(TODO_JSON.format(42, 'Some Task', False))
# {"id": 42,"title": Some Task,"completed:" False}

If you are using 2.6+, you can use do this:

print json.dumps(jsonStr, sort_keys=True, indent=2, separators=(',', ': '))

http://docs.python.org/2/library/json.html