RuntimeError, or user defined exception

[Cecil Westerhof]

I am creating a class that will call a user defined function on user
defined intervals. In my opinion it is an error when the function
takes more as 10% of interval, or more as half a second. What is
better: just using RuntimeError, or creating two exception classes for
this?

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Cecil Westerhof
Senior Software Engineer
LinkedIn: http://www.linkedin.com/in/cecilwesterhof