What is an exception and how to handle exception
What is an exception
Exceptions are used to represent an exceptional or illegal state of a program. For example, divide by zero is an exception, file not found is an exception too.
Python defines all kinds of exception we can use to indicate exceptional conditions. The following table lists some buildin exceptions.
| Class Name | Description |
|---|---|
| Exception | The root class for all exceptions |
| AttributeError | Raised when attribute reference or assignment fails |
| IOError | Raised when trying to open a nonexistent file (among other things) |
| IndexError | Raised when using a nonexistent index on a sequence |
| KeyError | Raised when using a nonexistent key on a mapping |
| NameError | Raised when a name (variable) is not found |
| SyntaxError | Raised when the code is ill-formed |
| TypeError | Raised when a built-in operation or function is applied to an object of the wrong type |
| ValueError | Raised when a built-in operation or function is applied to an object with correct type, but with an inappropriate value |
| ZeroDivisionError | Raised when the second argument of a division or modulo operation is zero |