def get_time_stamp(ct):
    local_time = time.localtime(ct)
    data_head = time.strftime("%Y-%m-%d %H:%M:%S", local_time)
　　 data_secs = (ct - int(ct)) * 1000
    time_stamp = "%s:%03d" % (data_head, data_secs)
    return time_stamp

print(get_time_stamp(1546244983.3656037))

輸出

2018-12-31
 
 16:30:05:069

或者

import datetime
 
print(datetime.datetime.now()) 
print(datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S:%f'))
print(datetime.datetime.now().strftime('%Y%m%d%H%M%S%f'))