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Time value does not match the format. ValueError in python

I am trying to convert a string to datetime object using the strptime function.
I am encountering a ValueError that says format doesn't match, so I did double checking and confirmed that the format in the string matches the format I am passing as the parameter for strptime.
I have also referenced this question: time data does not match format but there the month and year were swapped.
So does this only work with the '%y-%m-%d %H:%M:%S' format or is it dynamic as per the user input like in my case '%y-%m-%d-%H:%M:%S' ?
input:-
from datetime import datetime
stg = "2022-10-31-01:17:46"
do = datetime.strptime(stg, '%y-%m-%d-%H:%M:%S')
output
ValueError: time data '2022-09-31-01:17:46' does not match format '%y-%m-%d-%H:%M:%S'
Expected output:
#while printing 'do'
2020-09-31-01:17:46

You're almost there. You need %Y instead of %y since you're providing the year with the century (2022 instead of 22).
Your code would be
from datetime import datetime
stg = "2022-10-31-01:17:46"
do = datetime.strptime(stg, '%Y-%m-%d-%H:%M:%S')

How to convert the string to date time format?

I have the following string 20211208_104755, representing date_time format. I want to convert it to the python datetime format using datetime.strip() method.
mydatetime = "20211208_104755"
datetime_object = datetime.strptime(mydatetime, '%y/%m/%d')
However I am getting the following error.
ValueError: time data '20211208' does not match format '%y/%m/%d'

The second argument in strptime has to match the pattern of your datetime string. You can find the patterns and their meaning on https://docs.python.org/3/library/datetime.html
In your case, you can format it as
from datetime import datetime
mydatetime = "20211208_104755"
datetime_object = datetime.strptime(mydatetime, '%Y%m%d_%H%M%S')
print(datetime_object)
>>> 2021-12-08 10:47:55

what should work is to define how the mydatetime string is composed.
example:
%Y is the year (4 digits); check here for format (section strftime() Date Format Codes)
So in your example I would assume it's like this:
mydatetime = "20211208_104755"
datetime_object = datetime.strptime(mydatetime, '%Y%m%d_%H%M%S')
print (datetime_object)
result
2021-12-08 10:47:55
and
type(datetime_object)
datetime.datetime

Python how to check different date formats for multiple string values

I have a set of variables(epoch_time,normal_date,date_time,date_time_zone) which can be passed randomly and based on the string format, I am converting it into my required date format (%Y-%m-%d). My variable can be a string with epoch value or string with date timezone or string with datetime or only date. I have tried the following way and it is always going into the first item only in allowed_date_formats. Can someone suggest me a better approach or help me in resolving the issue.
from datetime import datetime
epoch_time='1481883402'
normal_date="2014-09-03"
date_time=str("2014-05-12 00:00:00")
date_time_zone=str("2015-01-20 08:28:16 UTC")
OP_FORMAT="%Y-%m-%d"
ALLOWED_STRING_FORMATS=["%Y-%m-%d %H:%M:%S %Z","%Y-%m-%d %H:%M:%S","%Y-%m-%d"]
def convert_timestamp(date_timestamp=None):
for format in ALLOWED_STRING_FORMATS:
if datetime.strptime(date_timestamp,format):
d=datetime.strptime(date_timestamp,"%Y-%m-%d")
else:
d = datetime.fromtimestamp((float(date_timestamp) / 1000.), tz=None)
return d.strftime(OP_FORMAT)
print(convert_timestamp(normal_date))
Error that i am getting is
ValueError: time data '2014-09-03' does not match format '%Y-%m-%d %H:%M:%S %Z'

You can use try-except for this.
def convert_timestamp(date_timestamp, output_format="%Y-%m-%d"):
ALLOWED_STRING_FORMATS=[
"%Y-%m-%d %H:%M:%S %Z",
"%Y-%m-%d %H:%M:%S",
"%Y-%m-%d",
]
for format in ALLOWED_STRING_FORMATS:
try:
d = datetime.strptime(date_timestamp,format):
return d.strftime(output_format)
except ValueError:
pass
try:
# unix epoch timestamp
epoch = int(date_timestamp) / 1000
return datetime.fromtimestamp(epoch).strftime(output_format)
except ValueError:
raise ValueError('The timestamp did not match any of the allowed formats')

Do you need to make sure that only specific formats are allowed?
Otherwise you might consider using the automatic parser from dateutil:
from dateutil import parser
normal_date="2014-09-03"
print(parser.parse(normal_date))

Error when converting date to specific format

I have the following format for my dates
1952-02-04 00:00:00
I need the format to be month/day/year
How do I go about this currently I have
if clientDob is not None:
clientDob = datetime.datetime.strptime(clientDob, '%Y-%m-%d').strftime('%m/%d/%y')
the error I get is
time data 'Birth Dt' does not match format '%Y-%m-%d'

Use
clientDob = datetime.datetime.strptime(clientDob, '%Y-%m-%d %H:%M:%S').strftime('%m/%d/%y')
for datetime parsing your string must match the source string exactly. It contains time-information, you need to match it.
import datetime
clientDob = "2018-12-21 12:13:14"
clientDob = datetime.datetime.strptime(clientDob, '%Y-%m-%d %H:%M:%S').strftime('%m/%d/%y')
print(clientDob)
Output:
12/21/18
Details: strftime-and-strptime-behavior

Conversion time from string

I have a problem with time conversion in Python:
I try to do this:
from datetime import datetime
date_object = datetime.strptime('12:29:31.181', '%H:%M:%S')
And I receive an error: "ValueError: unconverted data remains: .181"
Can you help me?

You need to add %f for microseconds:
In [335]:
from datetime import datetime
date_object = datetime.strptime('12:29:31.181', '%H:%M:%S.%f')
print(date_object)
1900-01-01 12:29:31.181000
Your format string has to consume all the characters in the passed in string, if any are still remaining then the ValueError is raised.