Are Python Exceptions Runtime Errors? Yes, Python exceptions are considered runtime errors. Most exceptions occur during runtime.Exceptions in Python are errors that occur when there is an abnormal scenario during the execution of a program, which terminates the execution abruptly, interrupting its normal flow. Examples of exceptions are ZeroDivisionError, IndexError,  ValueError, etc..Whereas, errors in Python are detected before the execution of the program, they include syntactical errors and other violations of the program rules. Examples of errors are SyntaxError,  IndentationError,  etc.  Exceptions are Raised at Runtime Exceptions occur when the execution of the program is interrupted because of issues like logical ... Read More

Custom exceptions in Python allow you to create meaningful error types that fit your application's needs. By adding error codes and error messages to custom exceptions, you can provide structured (organized) information when errors occur. Although Python has many built-in exceptions, custom exceptions are well-suited to explain specific problems in your program. Including error codes and messages, handling errors, and debugging your code. Creating a Custom Exception with Error Code You can create a custom exception by defining a class that inherits from Python's built-in Exception class. This allows you to include additional details, such as a custom error message ... Read More

Python uses the try-except block to handle errors during runtime. But as your program grows, handling exceptions can get messy with repeated code or too many nested blocks. Using cleaner methods for exception handling can reduce duplication, and make your code easier to manage. In this article, we explore better ways to handle exceptions in Python. Using Specific Exception Types It is best to catch specific exceptions like ValueError or FileNotFoundError instead of using a general except: block. This prevents hiding unexpected errors and improves debugging This approach avoids catching unrelated exceptions like KeyboardInterrupt or TypeError. Example In this ... Read More

In Python, the with statement is used when working with files or network connections. It makes sure that resources (files) are opened, used, and then closed properly, even if an error occurs during the process. If you want to catch any exceptions that happen inside a with block, you can wrap it in a try-except statement. Alternatively, you can use a custom context manager that handles exceptions on its own. Catching Exceptions Inside with Block Using try-except To catch errors that occur inside a with block, we need to place it within a try-except. This helps you to handle any ... Read More

Python threads do not automatically pass exceptions to the caller thread. To catch thread exceptions in the main thread, you can use custom thread classes, the ThreadPoolExecutor with futures, or a shared queue. Using a Wrapper with threading.Thread The easiest way to catch exceptions in a thread is to wrap the target function in a try-except block. You can then store the exception in a shared variable or object so it can be checked later from the main thread. Example In this example, we create a custom thread class that stores any exceptions in an instance variable. After the ... Read More

Only a single except clause in a try block is invoked. If you want the exception to be caught higher up then you will need to use nested try blocks.Let us write 2 try...except blocks like this:try: try: 1/0 except ArithmeticError as e: if str(e) == "Zero division": print ("thumbs up") else: raise except Exception as err: print ("thumbs down") raise errwe get the following outputthumbs down Traceback (most recent call last): File "C:/Users/TutorialsPoint1/~.py", line 11, in raise err File "C:/Users/TutorialsPoint1/~.py", line 3, in 1/0 ZeroDivisionError: division by zeroAs per python tutorial there is one and only one ... Read More

It is a general thumb rule that though you can catch all exceptions using code like below, you shouldn’t:try:     #do_something() except:     print "Exception Caught!"However, this will also catch exceptions like KeyboardInterrupt we may not be interested in. Unless you re-raise the exception right away – we will not be able to catch the exceptions:try:     f = open('file.txt')     s = f.readline()     i = int(s.strip()) except IOError as (errno, strerror):     print "I/O error({0}): {1}".format(errno, strerror) except ValueError:     print "Could not convert data to an integer." except:     ... Read More

Argparse is a Python module that helps you create easy-to-use command-line interfaces. When building these interfaces, it is important to handle invalid arguments properly to give clear feedback to users and prevent your program from crashing unexpectedly. There are several ways to handle invalid arguments in argparse. You can catch errors using try-except blocks, restrict allowed options with choices, validate inputs with custom functions and error messages, or control the number of arguments using nargs. Using these methods makes your command-line programs more reliable and user-friendly. Using try and except Blocks One simple method to handle invalid arguments is ... Read More

In Python, you can catch an exception and raise a new one, while keeping the original exception for more details. This helps when you want to change a low-level error into a clearer, higher-level error that fits your application better. Sometimes, catching a specific exception and raising a new one helps you to handle problems or give a clearer message. Python lets you do this using the raise NewException from OriginalException syntax. Rethrowing with a New Exception Type You can rethrow an exception using the from keyword to keep the original error details and traceback. This helps you provide ... Read More

Python allows you to run multiple tasks at the same time using threads. However, handling exceptions in threads can be tricky because exceptions that happen inside a thread don't get passed to the main thread by default. To deal with this, you can catch errors inside the thread's function or create a custom thread class to handle them. This helps you to find issues in threads and handle them properly in the main program. Exception Handling in Threads When an exception occurs inside a thread, it only affects that thread, and unless explicitly handled, it will be ignored silently. ... Read More