June 2017
Beginner
352 pages
8h 39m
English
Content preview from The Python Apprentice
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KeyError
A KeyError is raised when a look-up in a mapping fails.
You can see that here when we look up a non-existent key in a dict:
>>> codes = dict(gb=44, us=1, no=47, fr=33, es=34)>>> codes['de']Traceback (most recent call last): File "<stdin>", line 1, in <module> KeyError: 'de'
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I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.