Python dict() Function



The Python dict() function is used to create a new dictionary. A dictionary is a data structure that stores a collection of key-value pairs. Each key in the dictionary is unique and maps to a specific value. It is a mutable (changeable) and unordered structure.

Dictionaries are defined using curly braces {}, and each key-value pair is separated by a "colon". For example, you can use a dictionary to store information like names and corresponding ages.

Syntax

Following is the syntax of Python dict() function −

 dict(iterable) 

Parameters

This function accepts a list of tuples as a parameter where each tuple represents a key-value pair.

Return Value

This function returns a new dictionary object.

Example 1

In the following example, we are using the dict() function with keyword arguments to create a dictionary "person" with each key associated with a specific value −

 person = dict(name="Alice", age=30, city="New York") print('The dictionary object obtained is:',person) 

Output

Following is the output of the above code −

 The dictionary object obtained is: {'name': 'Alice', 'age': 30, 'city': 'New York'} 

Example 2

Here, we are using the dict() function to convert the list of tuples "data_tuples" into a dictionary by associating each tuple's first element as the key and the second element as the value −

 data_tuples = [("a", 1), ("b", 2), ("c", 3)] data_dict = dict(data_tuples) print('The dictionary object obtained is:',data_dict) 

Output

Output of the above code is as follows −

 The dictionary object obtained is: {'a': 1, 'b': 2, 'c': 3} 

Example 3

In here, we are using the dict() function along with a list comprehension to merge dictionaries in the "data_list" into a single dictionary −

 data_list = [{'name': 'Alice'}, {'age': 25}, {'city': 'London'}] data_dict = dict((key, value) for d in data_list for key, value in d.items()) print('The dictionary object obtained is:',data_dict) 

Output

The result obtained is as shown below −

 The dictionary object obtained is: {'name': 'Alice', 'age': 25, 'city': 'London'} 

Example 4

In this case, we use the dict() function in conjunction with the zip() function to pair up elements from the keys and values lists to create a dictionary −

 keys = ["name", "age", "city"] values = ["Bob", 28, "Paris"] person_dict = dict(zip(keys, values)) print('The dictionary object obtained is:',person_dict) 

Output

Following is the output of the above code −

 The dictionary object obtained is: {'name': 'Bob', 'age': 28, 'city': 'Paris'} 

Example 5

In this example, we first initialize an empty dictionary "empty_dict" using the dict() function. Subsequently, we populate the dictionary by adding key-value pairs −

 empty_dict = dict() empty_dict["name"] = "John" empty_dict["age"] = 30 empty_dict["city"] = "Berlin" print('The dictionary object obtained is:',empty_dict) 

Output

The result produced is as follows −

 The dictionary object obtained is: {'name': 'John', 'age': 30, 'city': 'Berlin'} 
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