If we need to send JSON from a client to a server, the simplest way with the Requests module is using the json parameter, specifying a dictionary structure in key-value format.

The main advantage of using this parameter is that it is not necessary to specify 'Content-Type' in the request. In the json response, we can see that it automatically returns this field with the 'application/json' value:

>>> import requests
 >>> response = requests.post('http://httpbin.org/post', json={"key": "value"})
 >>> response.status_code
 200
 >>> response.json()
 {'args': {},
 'data': '{"key": "value"}',
 'files': {},
 'form': {},
 'headers': {'Accept': '*/*',
 'Accept-Encoding': 'gzip, deflate',
 'Connection': 'close',
 'Content-Length': '16',
 'Content-Type': 'application/json',
 'Host': 'httpbin.org',
 'User-Agent': 'python-requests/2.4.3 CPython/3.4.0',
 'X-Request-Id': 'xx-xx-xx'},
 'json': {'key': 'value'},
 'origin': 'x.x.x.x',
 'url': 'http://httpbin.org/post'}