Common Examples - dict¶

Let us see some common examples while creating dict in Python. If you are familiar with JSON, dict is similar to JSON.

A dict can have key value pairs where key is of any type and value is of any type.
However, typically we use attribute names as keys for dict. They are typically of type str.
The value can be of simple types such as int, float, str etc or it can be object of some custom type.
The value can also be of type list or nested dict.
An individual might have multiple phone numbers and hence we can define it as list.
An individual address might have street, city, state and zip and hence we can define it as nested dict.
Let us see some examples.

# All attribute names are of type str and values are of type int, str or float
d = {'id': 1, 'first_name': 'Scott', 'last_name': 'Tiger', 'amount': 1000.0}

for key in d.keys():
    print(f'type of attribute name {key} is {type(key)}')

type of attribute name id is <class 'str'>
type of attribute name first_name is <class 'str'>
type of attribute name last_name is <class 'str'>
type of attribute name amount is <class 'str'>

for value in d.values():
    print(f'type of value {value} is {type(value)}')

type of value 1 is <class 'int'>
type of value Scott is <class 'str'>
type of value Tiger is <class 'str'>
type of value 1000.0 is <class 'float'>

d.update([('phone_numbers', [1234567890, 2345679180])])

{'id': 1,
 'first_name': 'Scott',
 'last_name': 'Tiger',
 'amount': 1000.0,
 'phone_numbers': [1234567890, 2345679180]}

for value in d.values():
    print(f'type of value {value} is {type(value)}')

type of value 1 is <class 'int'>
type of value Scott is <class 'str'>
type of value Tiger is <class 'str'>
type of value 1000.0 is <class 'float'>
type of value [1234567890, 2345679180] is <class 'list'>

d['address'] = {'street': '1234 ABC Towers', 'city': 'Round Rock', 'state': 'Texas', 'zip': 78664}

{'id': 1,
 'first_name': 'Scott',
 'last_name': 'Tiger',
 'amount': 1000.0,
 'phone_numbers': [1234567890, 2345679180],
 'address': {'street': '1234 ABC Towers',
  'city': 'Round Rock',
  'state': 'Texas',
  'zip': 78664}}

d['address']

{'street': '1234 ABC Towers',
 'city': 'Round Rock',
 'state': 'Texas',
 'zip': 78664}

type(d['address'])

dict

for value in d.values():
    print(f'type of value {value} is {type(value)}')

type of value 1 is <class 'int'>
type of value Scott is <class 'str'>
type of value Tiger is <class 'str'>
type of value 1000.0 is <class 'float'>
type of value [1234567890, 2345679180] is <class 'list'>
type of value {'street': '1234 ABC Towers', 'city': 'Round Rock', 'state': 'Texas', 'zip': 78664} is <class 'dict'>

Mastering Python

Common Examples - dict¶