str(trip_start_time.strftime('%s')) code example

Example 1: python datetime string

import datetime

today = datetime.datetime.now()
date_time = today.strftime("%m/%d/%Y, %H:%M:%S")
print("date and time:",date_time)

Example 2: python from timestamp to string

from datetime import datetime

timestamp = 1545730073
dt_object = datetime.fromtimestamp(timestamp)

print("dt_object =", dt_object)
print("type(dt_object) =", type(dt_object))

# Output

dt_object = "2018-12-25 09:27:53"
type(dt_object) = <class 'datetime.datetime'>