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Python Python Basics Functions and Looping Raising Exceptions

Cecilia Rossi García
Cecilia Rossi García
2,251 Points

Questions about variable 'err'

How does the variable 'err' in the try block reference the argument in 'raise ValueError'?

Unclear how 'as err' works to reference 'raise ValueError' argument versus the argument in 'except ValueError' ...if that even makes sense...

1 Answer

Steven Parker
Steven Parker
215,954 Points

I assume you meant to say "the variable 'err' in the except block..."

The argument to a "raise" is used as the contents of the "message" attribute of the exception object that is created.

The "AS" keyword stores a reference to the exception object in the named variable ("err" in this case). Referencing the object as a string (such as with "print") will return the contents of the "message" attribute.