How to implement CSV to JSON Conversion in Python

1import csv
2import json
3from typing import List, Dict, Any
4
5# CSV to JSON
6def csv_to_json(csv_file: str, json_file: str) -> None:
7    rows = []
8    with open(csv_file, 'r', encoding='utf-8') as f:
9        reader = csv.DictReader(f)
10        for row in reader:
11            rows.append(row)
12    
13    with open(json_file, 'w') as f:
14        json.dump(rows, f, indent=2)
15
16csv_to_json('data.csv', 'data.json')
17
18# JSON to CSV
19def json_to_csv(json_file: str, csv_file: str) -> None:
20    with open(json_file, 'r') as f:
21        data = json.load(f)
22    
23    if not data:
24        return
25    
26    keys = data[0].keys()
27    with open(csv_file, 'w', newline='') as f:
28        writer = csv.DictWriter(f, fieldnames=keys)
29        writer.writeheader()
30        writer.writerows(data)
31
32json_to_csv('data.json', 'output.csv')
33
34# With data transformation
35def csv_to_json_transform(csv_file: str) -> List[Dict[str, Any]]:
36    rows = []
37    with open(csv_file, 'r', encoding='utf-8') as f:
38        reader = csv.DictReader(f)
39        for row in reader:
40            transformed = {
41                'id': int(row['id']),
42                'name': row['name'].title(),
43                'email': row['email'].lower(),
44            }
45            rows.append(transformed)
46    return rows