Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community!

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

Python Dates and Times in Python (2014) Let's Build a Timed Quiz App Harder Time Machine

'time_string' is an invalid keyword argument for this function'

'time_string' is an invalid keyword argument for this function. Not sure why we need key word arguments in this case and how to implement them

import datetime

starter = datetime.datetime(2015, 10, 21, 16, 29)

# Remember, you can't set "years" on a timedelta!
# Consider a year to be 365 days.

## Example
# time_machine(5, "minutes") => datetime(2015, 10, 21, 16, 34)

def time_machine(time_int, time_string):
    if time_string == "years":
        time_int *= 365
        time_string = "days"
    return starter + datetime.timedelta(time_string=time_int)

2 Answers

Steven Parker
Steven Parker
228,096 Points

As the hint says, "time_string" is not a valid argument name. Valid arguments have names like "minute", "hour", "week", etc. For more details, see the Python documentation page for timedelta.

If you want to create a kwarg using a variable for the argument name, you could pack it into a dictionary and then apply the unpacking operator ("**") on the dictionary.

'''def time_machine(time_int, years): if years == 'years': time_int = 365 years = 'days' return starter + datetime.timedelta(*{years : time_int}) '''