import pandas as pd
psr = pd.Series(['python', 'java', 'c++', 'c', None, 'php' ])
idx = pd.date_range('2020-5-15', periods = 6)
psr.index = idx
print(psr)
'''
run:
2020-05-15 python
2020-05-16 java
2020-05-17 c++
2020-05-18 c
2020-05-19 None
2020-05-20 php
Freq: D, dtype: object
'''