#exercise 19,20,21,22
import numpy as np
import pandas as pd
'''---19ser = pd.Series(['how', 'to', 'kick', 'ass?'])
ser1= pd.Series([len(i) for i in ser])
print(ser1)'''
'''---20ser = pd.Series([1, 3, 6, 10, 15, 21, 27, 35])
print(ser.diff())'''
'''---21ser = pd.Series(['01 Jan 2010', '02-02-2011', '20120303', '2013/04/04', '2014-05-05', '2015-06-06T12:20'])
print(pd.to_datetime(ser))'''
