I would like to handle the following Exception from py_vollib/py_lets_be_rational in specific way. Tried this without success: what am I doing wrong? any help would be appreciated. Answer Looking at the implementation, you’re missing the period at the end of the sentence: I don’t see the point in this check because that will always be the message the exception is
Tag: exception
What is the simplest way to retry a Django view upon an exception being raised?
I want to rerun a Django view function if a certain exception is raised (in my case a serialization error in the underlying database). I want it to run with exactly the same parameters, including the same request object – as if the client had re-requested the URL. There are many database queries in the view, and the exception could
How to get python default exception message in exception handling
When I handle an exception in python It prints I expect it to print Is there a way to retrieve the default error message ? Answer Instead of this: do this: or just this:
Python “raise from” usage
What’s the difference between raise and raise from in Python? which yields and which yields Answer The difference is that when you use from, the __cause__ attribute is set and the message states that the exception was directly caused by. If you omit the from then no __cause__ is set, but the __context__ attribute may be set as well, and
Multiple try codes in one block
I have a problem with my code in the try block. To make it easy this is my code: Is something like this possible? Answer You’ll have to make this separate try blocks: This assumes you want to run code c only if code b failed. If you need to run code c regardless, you need to put the try
Python: Catching specific exception
I want to catch a specific ValueError, not just any ValueError. I tried something like this: But it raises a SyntaxError: can’t assign to literal. Then I tried: But it raises the exception, even if it is the one I want to avoid. Answer in except ValueError,e, e is an instance of the exception, not a string. So when you
Handling a timeout error in Python sockets
I am trying to figure out how to use the try and except to handle a socket timeout. The way I added the socket module was to import everything, but how do I handle exceptions? In the documentation it says you can use socket.timeouterror, but that doesn’t work for me. Also, how would I write the try exception block if
Why do we need the “finally” clause in Python?
I am not sure why we need finally in try…except…finally statements. In my opinion, this code block is the same with this one using finally: Am I missing something? Answer It makes a difference if you return early: Compare to this: Other situations that can cause differences: If an exception is thrown inside the except block. If an exception is
Extract traceback info from an exception object
Given an Exception object (of unknown origin) is there way to obtain its traceback? I have code like this: How can I extract the traceback from the Exception object once I have it? Answer The answer to this question depends on the version of Python you’re using. In Python 3 It’s simple: exceptions come equipped with a __traceback__ attribute that
“except” statement with same exception class as parameter twice
In Python, how can I use except block with same exception name twice in try/except statements without need to wrap code into one more try/except block? Simple example (here each call of pages.get may raise the exception): For now, in my Django app I do handling like this (but I don’t want “extra” try block here): Any handling code better