Calcul du temps python (milli secondes)

Question

Comment calculer les millisecondes, à partir du code ci-dessous.

a = datetime.datetime.now() 
b = datetime.datetime.now() 
c = b - a 

>>> c 

>>> c.days 
0 
>>> c.seconds 
4 
>>> c.microseconds 

Answer 1

milliseconds = (c.days * 24 * 60 * 60 + c.seconds) * 1000 + c.microseconds/1000.0 

Answer 2

Ou, nouveau depuis 2.7:

c.total_seconds()*1000 

(https://docs.python.org/2/library/datetime.html)