Overview of the subscript operator:
- Using the subscript operator a value corresponding to a key from a Python dictionary instance can be retrieved.
- A new value can be added to or an existing value can be updated to a Python dictionary instance using the subscript operator.
Parameters:
dict_key_in - The key for which the value to be added/updated/retrieved.
Return Value:
The value corresponding to the dict_key_in parameter is returned in case of retrieval.
Exception Handling:
If the key value is not found in the dictionary a KeyError is raised. For the subclasses of dict, the function __missing__ will be invoked if one is defined. Otherwise, KeyError is raised.
Note:
__missing__ function is typically defined by a subclass to return a default value when the lookup for the key in a Python dictionary fails.
Example:
|
>>> dict = {'PyCon2016':'Portland-OR','SciPy 2016':'Austin-TX','EuroPython 2016':'Bilbao'}
>>> dict['PyCon2016'] 'Portland-OR' |