Data Structures

Dictionaries

Dictionaries are data structures that allow you to define custom indexes or keys.

In other languages, dictionaries are referred to as hash maps, hash tables, or associative arrays.

Dictionaries begin and end with curly braces {} and each key/value pair is separated by a comma ,. You define keys and their corresponding values separated by a colon :

a = {
  'name': 'Guido van Rossum',
  'yob': 1956
}

Indexing

You can index into a dictionary using the defined keys, which is often easier than remembering numeric indexes

a['name']
a['yob']

Insert

Use the assignment operator = to insert new items into an existing dictionary

a['job title'] = 'BDFL'

Update

Use the assignment operator = to update dictionary items

a['job title'] = None

Delete

Use the del keyword to delete items from a dictionary

del a['job title']