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

Bummer! `time_machine` didn't return the right datetime.

Not sure why my codes got this error

time_machine.py
import datetime
from datetime import timedelta

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(arg1: int, arg2: str):
    if arg2 == "hours":
        return (starter - timedelta(days=arg1/24))
    elif arg2 == "years":
        return (starter - timedelta(days=arg1 * 365))
    elif arg2 == "days":
        return (starter - timedelta(days=arg1))
    elif arg2 == "minutes":
        return (starter - timedelta(seconds=arg1 * 60))

2 Answers

Steven Parker
Steven Parker
231,269 Points

Your calculations are in the wrong direction.

When the instructions say to calculate the "duration from the starter ....", they mean the time that is the specified units after the "starter" time. So you need to add the deltas instead of subtracting them.

sorry for mistake