Python: Dictionaries



For example, a database of phone numbers could be stored using a dictionary like this:

phonebook = {}
phonebook["John"] = 938477566
phonebook["Jack"] = 938377264
phonebook["Jill"] = 947662781

Alternatively, a dictionary can be initialized with the same values in the following notation:

phonebook = {
    "John" : 938477566,
    "Jack" : 938377264,
    "Jill" : 947662781

Iterating over dictionaries

Dictionaries can be iterated over, just like a list. However, a dictionary, unlike a list, does not keep the order of the values stored in it. To iterate over key value pairs, use the following syntax:

for name, number in phonebook.iteritems():
    print "Phone number of %s is %d" % (name, number)

Removing a value

To remove a specified index, use either one of the following notations:

del phonebook["John"]