yield_curve_starter.py

import sys
from datetime import date
import quandl

'''sys.argv is a module that has all the inputs of a command line in a list
so for example if you run

python main.py "2018-1-25"
sys.argv would be [main.py', '2018-1-25']

sys.argv is generally used when you expect another developer to run your tool on the command line. Obviously you don't
want it to be used by a regular person. For them you would provide a web UI where they can fill in a form
'''
# Set the year_string, month_string, day_string by splitting up the sys.arg[1] using the dash limeter
year_string, month_string, day_string = sys.argv[1].split('-')
input_date_as_date_object = date(int(year_string), month=int(month_string), day=int(day_string))
data_frame = quandl.get('USTREASURY/YIELD')
print(data_frame.loc[input_date_as_date_object])