Python 3 Programming Tutorial - Try and Except error Handling

In this Python 3 programming tutorial, we cover the Try and Except statements, which are used for error handling. These statements work similarly to the if-else, where if the Try runs, the except will not run. If the Try fails, then the exception will run with the error that was just generated in the try.

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[sofoboachie]

Thanks, everyone else just gives the Try Exception format without explaining the importance of the programmer thinking ahead and employing something like an If-Else statement. Very good

[fedora]

x = 0
y = 2

try:
print(y/x)

except Exception as e:
print("Error in your code " + str(e))

[cybernoodleowww]

Everything works fine till I add the if, else. After that the problem is if I enter say GreeN even though we have
the whatColor.lower()) to allow the use of upper case or lower case, it doesn't work for me. Again when I
use the if else, other wise it all works fine. Any help as to why?

[TheGamezAM]

Can anybody explain the raise keyword?

[mohammadummair]

my python program shows "inconsistent use of tabs and spaces in indentation" please help!

[mango_]

Hello, Sentdex, do you know why excepton function in the code write as below cannot work? I input word not in the list, however, there is no exception posted. Thank you.

y=["s", "A", "siri", "b", "a"]
try:
word=input("input the word you want:\n")
if word in y:
indexof=y.index(word)
print(word)
# else:
# print("word not in the list")
except Exception as e:
print(e)

[Kisuke]

how does he get 'pink' is not on the list? I have only "continuing". Absolute beginner.

[gwbrown]

So I tried to set up data validation to test to see if the user input was a valid int or float. The only way I got it to work was with the try / except. I even tried the isinstance to return true or false but because user input is automatically set as string it didnt work. Any help would be great, as of right now I'm converting the user I put into float and doing the try except on the value error because letters cant be converted to float.

[Hellomynamesolly]

@Sentdex please post your ERC20 address up. Your videos are some of the most helpful and comprehensive education tools I've come across and you deserve to be rewarded :)

[farzadk.]

Hi, if the else is triggered and the program outputs 'color not found or is not a color', is there a command (like go to) that we can use to jump back to the input line in the code and ask the user to input the color again? (and do this in a loop, until the user inputs something correct)

[secondmodu]

at the 0:29 you have ValueError, but why do you use NameError for exception?

[coltonvevomixtapes]

Heres my source code:
hi = int(input("Input a number "))
yo = int(input("Input a second number "))


try:
print(hi + yo)

except Exception as e:
print(e)

print('continuing')



How can i make it so that this program doesn't crash when I enter a string in one of the values?

[b]

can you make a VIDEO about assertion please.

[pythonprogrammer]

Eh! Stop Smashing your keyboard and Let the dog sleep!  2:35
Amazing tutorial as always :)

[Zed]

can you use a ide with a darker theme? just like pycharm or sublime. because the white theme of your ide makes my eyes burn, probably not just me

[uceee]

for some reason i got that error
['20-02-16', '21-08-19']
['red', 'blue']
What colour date of do you want to know?red
<built-in method lower of str object at is not in list
continuing thanks to exception

it works ok without expection


try:
whatColor = input("What colour date of do you want to know?")
coldex = colors.index(whatColor.lower)
theDate = dates[coldex]
print("The date of", whatColor, "is a", theDate)
'assignes colour to date'
"lower changes letters to lowercase"
except Exception as e:
print(e)
print("continuing thanks to exception")

[GPCTM]

except(OverflowError, ValueError):

except TypeError:

except AttributeError:
...

[aaronsiew]

May I know what is the meaning of e?sorry, I'm new in python.

[laxminarasimhasrinivas]

Hi i am getting error like this
Traceback (most recent call last):
File "csv", line 16, in <module>
whoseSal = input("whose salary you want to know ?")
File "<string>", line 1, in <module>
NameError: name 'Rajiv' is not defined

Given CSV file Data:
Srinu, IND, Analyst, 50000
Rajiv, CHI, Prorammer, 75000

Chintu, USA, Admin, 40000
Hara, JAP, Associate, 50000

while running this code

import csv
with open("empd.csv") as csvfile:
csvread = csv.reader(csvfile, delimiter=', ')
names = []
sals = []

for row in csvread:
name = row[0]
sal = row[3]
names.append(name)
sals.append(sal)

print(names)
print(sals)

whoseSal = input("whose salary you want to know ?")
nameedx = names.index(whoseSal)

the_sal = sals[nameedx]
print("salary of ", whosesal, "is ", the_sal)


Can you help me to solve this problem.

[kurisu]

mr. sentdex why did you choose win 10, i like win 8.1 better though