code: def parse_timedelta(str):
  	
  	deltas = (_parse_timedelta_part(part.strip()) for part in str.split(','))
  	return sum(deltas, datetime.timedelta())
docs: Take a string representing a span of time and parse it to a time delta.
  	Accepts any string of comma-separated numbers each with a unit indicator.
  
  	>>> parse_timedelta('1 day')
  	datetime.timedelta(days=1)
  
  	>>> parse_timedelta('1 day, 30 seconds')
  	datetime.timedelta(days=1, seconds=30)
  
  	>>> parse_timedelta('47.32 days, 20 minutes, 15.4 milliseconds')
  	datetime.timedelta(days=47, seconds=28848, microseconds=15400)
  
  	Supports weeks, months, years
  
  	>>> parse_timedelta('1 week')
  	datetime.timedelta(days=7)
  
  	>>> parse_timedelta('1 year, 1 month')
  	datetime.timedelta(days=395, seconds=58685)
  
  	Note that months and years strict intervals, not aligned
  	to a calendar:
  
  	>>> now = datetime.datetime.now()
  	>>> later = now + parse_timedelta('1 year')
  	>>> diff = later.replace(year=now.year) - now
  	>>> diff.seconds
  	20940