Using datetime with another function

Question

My error-handling works, but something is wrong.

import datetime
def d(date):
    return datetime.datetime.strptime(date, "%d/%m/%Y")


def test(prompt):
    while True:
        try:
            value = input(prompt)
            a = d(value)
            break
        except ValueError or TypeError:
            print("Wrong format")
    return a

b = test("Write date")

def func():
    a = d(b)
    if d('1/12/2020') <= a <= d('28/02/2021'):
        print("ok")
    else:
        print("no")

func()

When I put b in another function I get:

return datetime.datetime.strptime(datumet, "%d/%m/%Y")
TypeError: strptime() argument 1 must be str, not datetime.datetime.

But without error handling it works. What can be wrong with the code?

The error clearly comes from `func`, which you don't show us, so we can't help you. Either way, `datumet` is already `datetime` according to the error, so you don't need to call `strptime` — DeepSpace, Nov 18 '20 at 17:19
You need to add error handling for `TypeError` somewhere — either in the `d()` function itself or everywhere an attempt is made to use it. — martineau, Nov 18 '20 at 17:40
@martineau, I placed: except ValueError or TypeError (in the test-function) but it did not work. — , Nov 18 '20 at 17:43
Without see what changes you made, I am unable comment further… — martineau, Nov 18 '20 at 17:49
This `except ValueError or TypeError:` is not the correct way of catching multiple exceptions. See [Catch multiple exceptions in one line (except block)](https://stackoverflow.com/q/6470428/2745495). — Gino Mempin, Nov 19 '20 at 00:21

Kirk Strauser · Accepted Answer · 2020-11-18T17:47:05.000

0

Your test function returns a datetime object. In the func function, you're trying to take the datetime object you've passed in and call the d() function on it, but d() expects a string as its input.

Look at this line:

b = test("Write date")

b is a datetime, because that's what test returned to it. Then when you call

func(b)

you're passing in that datetime. Then, inside func you have:

if d('1/12/2020') <= d(date) <= d('1/12/2021'):

The first call to d('1/12/2020') works because d expects to get a string. The second call, d(date) fails, because date isn't a string: it's the datetime you passed in. The third call to d('1/12/2021') would succeed but you're never getting that far because the second call fails.

edited Nov 18 '20 at 17:47

answered Nov 18 '20 at 17:40

Kirk Strauser

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I see so what should I do? – Nov 18 '20 at 17:44
Now I understand what you mean!! But how should I fix the problem? I need to pass in parameter – Nov 18 '20 at 17:49
You you _have_ to call `d(date)` inside `func` if it's already a datetime? – Kirk Strauser Nov 18 '20 at 17:53
Do you mean like this? I edited the code? It still did not work – Nov 18 '20 at 18:00
What happens if you try the comparison directly on the `date` value you pass into `func`, instead of trying to call `d(date)`? – Kirk Strauser Nov 18 '20 at 18:53
It worked! thank you!! – Nov 18 '20 at 20:53

Using datetime with another function

1 Answers1