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Python

Posted by alexandracoder0809
alexandracoder0809
2,606 Points

wiki.py: Need an explanation of the code in the video

Good Afternoon!

I have difficulties to understand this code example from this video: https://teamtreehouse.com/library/dates-and-times-in-python/dates-and-times/wikipedia-links

Here is the teacher's code:

import datetime

answer_format = "%m/%d"
link_format = "%b_%d"
link = "https://en.wikipedia.org/wiki/{}"



while True:
    answer = input("What date would you like? Please use the MM/DD format. Enter 'quit' to quit.")
    if answer.upper() == "QUIT":
        break


    try:
        date = datetime.datetime.strptime(answer, answer_format)
        output = link.format(date.strftime(link_format))

        print(output)
    except ValueError:
        print("That's not a valid date. Please try again.")

I have several questions:

1.) Can somebody explain the whole code in the try block? And break the steps down for me? 2.) Can somebody explain me when to use what? (Like I know all these different datetime methods but I mix them all the time up.)

Thanks in Advance, Alexandra

1 Answer

Steven Parker
Steven Parker
243,656 Points
Steven Parker
Steven Parker
243,656 Points

I'll try to break down those lines:

        date = datetime.datetime.strptime(answer, answer_format)
#                                         answer                 <- the string typed in
#                                                 answer_format  <- the format it should be in
#              datetime.datetime.strptime(answer, answer_format) <- convert it to a date
#                                                                   (any problems converting may
#                                                                    cause a ValueError exception.)
#       date =                                                   <- save it in this variable
        output = link.format(date.strftime(link_format))
#                            date                                <- the date from above
#                                          link_format           <- the format we want it in
#                            date.strftime(link_format)          <- convert it to a string
#                link                                            <- a string with placeholder
#                link.format(date.strftime(link_format))         <- "fill in the blank"
#       output =                                                 <- save it in this variable

I can never remember every function, either! Make yourself a "cheat sheet", or find a good documentation summary online and add it to your bookmarks.

alexandracoder0809
alexandracoder0809
2,606 Points

Thank you really much! Now I understand it better!