I'm getting Key error in python

python dictionary
David Liaw picture David Liaw · Apr 12, 2012 · Viewed 701.4k times · Source

In my python program I am getting this error:

KeyError: 'variablename'

From this code:

path = meta_entry['path'].strip('/'),

Can anyone please explain why this is happening?

Answer

RanRag picture RanRag · Apr 12, 2012

A KeyError generally means the key doesn't exist. So, are you sure the path key exists?

From the official python docs:

exception KeyError

Raised when a mapping (dictionary) key is not found in the set of existing keys.

For example:

>>> mydict = {'a':'1','b':'2'}
>>> mydict['a']
'1'
>>> mydict['c']
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
KeyError: 'c'
>>>

So, try to print the content of meta_entry and check whether path exists or not.

>>> mydict = {'a':'1','b':'2'}
>>> print mydict
{'a': '1', 'b': '2'}

Or, you can do:

>>> 'a' in mydict
True
>>> 'c' in mydict
False

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