Crear fecha a partir de un String

import pandas as pd
startdate = "10/10/2018"
my_date = pd.to_datetime(startdate)
print(my_date.strftime("%Y-%m-%d"))

2018-10-10

Crear fecha actual

import datetime
my_date = datetime.datetime.now()
print(my_date.strftime("%Y-%m-%d"))

2018-10-10

Incrementar días

enddate = my_date + pd.DateOffset(days=5)
print(enddate.strftime("%Y-%m-%d"))

2018-10-15

Reducir días

enddate = my_date - pd.DateOffset(days=5)
print(enddate.strftime("%Y-%m-%d"))

2018-10-05

Pasar fecha a numérico: Unit timestampo

print("Unix Timestamp: ", (time.mktime(my_date.timetuple())))

1538690400.0