PRAW: Python can print Reddit comment variable but not return it

Question

I've read this answer, a second answer and also this answer about mixing return with loops and lastly this answer about returns, but they don't apply here.

Problem: I can print the date of comment, but I can't seem to "return" it properly. Ultimately, I need to add the dates to a list.

import datetime
def get_date(submission):
    time = submission.created
    return datetime.datetime.fromtimestamp(time)

authors_list = []
date_list = []

# Problem is here: 
for comment in submission.comments.list():
    authors_list.append(comment.author) # works fine!
    date_list.append(get_date(comment)) # does not work

print authors_list 
print date_list # does not work

I expect the date list to return

[2013-06-22 12:28:54, 2014-06-22 12:28:54, 2015-06-22 12:28:54]

But instead I get:

[datetime.datetime(2013, 6, 22, 3, 4, 7), datetime.datetime(2013, 6, 22, 10, 33, 47)...]

What I've tried:

Tried saving the date to a variable within the loop, but it doesn't work: (I get the same output as above)

date_list = [ ]
for comment in submission.comments.list():
    a_date = get_date(comment)
    date_list.append(a_date)
print date_list

>>> [datetime.datetime(2013, 6, 22, 3, 4, 7) ...]

How do I fix this? And can anyone explain why this happens? Thanks!

Context: If its of any relevance, I'm using praw v5.2.0 to extract data from the Reddit API.

Your definition of "doesn't work" seems a bit misleading. Your question is actually about converting a datetime to a string? — roganjosh, Oct 30 '17 at 09:31
The thing you "expect the date list to return" is not a valid Python literal. You're getting a list of datetimes, which is what you seem to want, so what's the *problem*? — jonrsharpe, Oct 30 '17 at 09:31
@LSelter yes, printing the returned list returns the desired answer (ie. 2013-06-22 12:28:54 ... ). However I want to append it to a list and I can't do that if I'm just printing the result — angsty_robot, Oct 30 '17 at 09:33
@jonrsharpe I had a function to convert the dates to "dd-mm-yyyy", which works when I print it. the _problem_ is that it's not returning this same format when I try to return(?) with `date_list.append(get_date(comment))`. Why does the format change, and how can I change it back? (edit) sorry if this question sounds awkward, I'm not sure how to phrase it — angsty_robot, Oct 30 '17 at 09:38
You may be being confused by the fact that when you print a datetime directly you see the `str`ing format, whereas when you print it inside the list you see its `repr`esentation format. But they're the same object; if you want strings, you need to be explicit about that. — jonrsharpe, Oct 30 '17 at 09:44

L Selter · Accepted Answer · 2017-10-30T09:47:23.083

If I understand you correctly, and you just want to store the string representation of the datetime object try this:

# Problem is here: 
for comment in submission.comments.list():
    authors_list.append(comment.author) # works fine!
    date_list.append(str(get_date(comment))) # should now work as expected

In your original code you added the datetime.datetime object you your list and returned the, apparently you are after just having a list of strings, so wrapping you get_date() call in a str() call achieves this. although it may be better to do this later if you still need access to the datetime object functionality later, outside of this function. and convert to string at the point of use.

thanks!! It works :-) If you have a moment, do you mind explaining what went wrong with mine? — angsty_robot, Oct 30 '17 at 09:41

score 0 · Answer 2 · answered Oct 30 '17 at 09:41

0

You can convert datatime.datatime object to String adding strftime to return sentence.

datetime.datetime.fromtimestamp(time).strftime("%Y-%m-%d %H:%M:%S")

answered Oct 30 '17 at 09:41

Takumi Tsuji

37
7

PRAW: Python can print Reddit comment variable but not return it

2 Answers2