Guys, what I said is the doc in help(datetime.timestamp) is 'Return POSIX timestamp as float.' So I assumed it is irrelevant to time zone, considering POSIX timestamp's definition. If it is then datetime.now and datetime.utcnow should return the same timestamp. But datetime.now().timestamp return a correct timestamp which I checked in the website https://www.unixtimestamp.com/ but datetime.utcnow().timestamp did not.

:)