# import necessary libraries
import pandas as pd
import arrow
# create sample series
dates = pd.Series(["2022-01", "2022-02", "2022-03", "2022-04"])
# use pandas date_range() function
new_dates = dates.apply(lambda x:
arrow.get(x + "-04", "YYYY-MM-DD"))
# print the results
print(new_dates)