datetime arithmeticis (addition)

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examples/datetime/add_timedelta.py

import datetime

timestamp = "2013-12-29T11:23:45"
ts = datetime.datetime.strptime(timestamp, '%Y-%m-%dT%H:%M:%S')
print(type(ts))
diff = datetime.timedelta(days = 3)
print(diff)
nts = ts + diff
print(type(nts))
print(ts)
print(nts)       # 2014-01-01 11:23:45