try…except…finally in Python: Way to Handle and Manage Errors.
In Python, the 'try...except...finally' statement is an extended version of the 'try...except' statement that includes a 'finally' block. The 'finally' block is executed regardless of whether an exception occurred or not. It provides a way to define cleanup actions that must be performed, such as releasing resources or closing files, irrespective of the presence of exceptions.
In simple terms, 'finally' is like a compulsory question in exams that has to be attended no matter what and in the same way, whether there is an error or not, 'finally' block will get executed. Let's see the syntax and working of try…except…finally in Python.
Syntax of try…except…finally in Python:
The try…except…finally statement is similar to control flow statements like for loop or while loop and its syntax too is similar.
>>> try:
>>> # Code that might raise an exception
>>> # ...
>>> except ExceptionType1:
>>> # Code to handle ExceptionType1
>>> # ...
>>> except ExceptionType2:
>>> # Code to handle ExceptionType2
>>> # ...
>>> finally:
>>> # Code that always executes, regardless of whether an exception occurred or not
>>> # ...
Working of try...except…finally in Python:
- The statements within the 'try' block are executed one by one.
- If an exception occurs during the execution of any statement within the 'try' block, the remaining statements within the block are skipped, and the control is transferred to the appropriate 'except' block.
- The exception is compared with the specified exception types in the 'except' blocks. If the exception matches any of the exception types listed in the 'except' blocks, the corresponding block is executed.
- After executing the except block, the control proceeds to the 'finally' block.
- The 'finally' block is always executed, regardless of whether an exception occurred or not. It is typically used for cleanup tasks and releasing resources that need to be performed no matter what.
- After executing the 'finally' block, the program continues its execution from the next statement after the entire 'try...except...finally' statement. If there is no 'finally' block, the program proceeds from this point.
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