Complete the function so that it returns the number of seconds that have elapsed between the start and end times given.  
##### Tips:
- The start/end times are given as Date (JS/CoffeeScript), DateTime (C#), Time (Nim), datetime(Python) and Time (Ruby) instances.  
- The start time will always be before the end time.
def elapsed_seconds(start, end):
    start = str(start).replace('-', ' ').replace(':', ' ').split(' ')
    end = str(end).replace('-', ' ').replace(':', ' ').split(' ')
    res = [ int(end[i]) - int(start[i]) for i in range(6) ]
    return res[2] * 86400 + res[3] * 3600 + res[4] * 60 + res[5]
def elapsed_seconds(start, end):
    start = str(start).replace('-', ' ').replace(':', ' ').split(' ')
    end = str(end).replace('-', ' ').replace(':', ' ').split(' ')
    res = [ int(end[i]) - int(start[i]) for i in range(6) ]
    return res[2] * 86400 + res[3] * 3600 + res[4] * 60 + res[5]