Answering question on StackOverflow I've found next example in docs of datetime.timestamp() ( https://docs.python.org/3/library/datetime.html#datetime.datetime.timestamp ) which returns UTC timestamp:

timestamp = (dt - datetime(1970, 1, 1)) / timedelta(seconds=1)

While it works I think there's more explicit way using timedelta.total_seconds() :

timestamp = (dt - datetime(1970, 1, 1)).total_seconds()

In same article few lines above there's example using total_seconds() so I think it will be good to use same method in both examples.