python requests module - set key to null
There is no session-level JSON parameter, so the merging rules don't apply.
In other words, the json keyword argument to the session.request() method is passed through unchanged, None values in that structure do not result in keys being removed.
The same applies to data, there is no session-level version of that parameter, no merging takes place. If data is set to a dictionary, any keys whose value is set to None are ignored. Set the value to '' if you need those keys included with an empty value.
The rule does apply when merging headers, params, hooks and proxies.
from the requests documentation :

Remove a Value From a Dict Parameter
Sometimes you’ll want to omit session-level keys from a dict parameter. To do this, you simply set that key’s value to None in the method-level parameter. It will automatically be omitted.

I need the data with key's value as None to take the Json value null instead of being removed.
Is it possible ?
edit : This seems to happen with my request data keys. While they are not session-level the behaviour of removing is still the same.