Question

Just studying data structures in python for a project and can’t work out the difference in a dictionary and a data structures in this form:

class Address:

    def __init__(self, house_number, house_street, house_city,
                 house_county, house_postcode):
        self.number = house_number
        self.street = house_street
        self.city = house_city
        self.county = house_county
        self.postcode = house_postcode

    def __repr__(self):
        return ('<Class: \'Address\', '+ str(self.number) + ' ' +
                self.street + ' ' + self.city + ' ' +
                self.county + ' ' + self.postcode + '>')


## Creates an object Address and assign it to a variable
my_address = Address(1, 'abc', 'def', 'ghi', 'jkl')

## Print the object My_address
print 'Address object:', my_address

print 'house number:', my_address.number

## change house number
my_address.number = 555

print 'NEW house number:', my_address.number

The code sample is modified from sample code given in a lecture at university of york.

Answer 1

A python dict is a highly optimized hash table, which is a data structure.

So, to put it differently, a python dict is one example of a data structure. So are the set, list, string and unicode types. A custom class is again another data structure, one that is highly customizable to your application needs.

From the WikiPedia entry on Data structure:

In computer science, a data structure is a particular way of storing and organizing data in a computer so that it can be used efficiently.