Python dict Builtin Function Examples

Python dict

Python dict() builtin function creates a Python dictionary object from the data given via arguments.

In this tutorial, we will learn about the syntax of Python dict() function, and learn how to use this function with the help of examples.

Syntax

The syntax of dict() function with only keyword arguments as parameter is

dict(**kwargs)

The syntax of dict() function with a mapping (could be another dictionary) and keyword arguments as parameters is

dict(mapping, **kwargs)

The syntax of dict() function with an iterable and keyword arguments as parameters is

dict(iterable, **kwargs)

where

Parameter	Required/Optional	Description
**kwargs	Optional	None, One or Multiple keyword arguments.
mapping	Optional	A dictionary object.
iterable	Optional	An iterable object. Could be a tuple, list, set, etc., or any object that implement __iter__() method.

Returns

The function returns object of type dict.

Examples

1 dictkwargs

In this example, we will give keyword arguments to dict() function.

Python Program

myDictionary = dict(a=1, b=3, c=5)
print(myDictionary)

Output

{'a': 1, 'b': 3, 'c': 5}

2 dictmapping, kwargs

In this example, we will give a dictionary for mapping parameter and keyword arguments to dict() function.

Python Program

mapping = dict(m=4, p=5)
myDictionary = dict(mapping, a=1, b=3, c=5)
print(myDictionary)

Output

{'m': 4, 'p': 5, 'a': 1, 'b': 3, 'c': 5}

3 dictiterable, kwargs

In this example, we will give a list for iterable parameter and keyword arguments to dict() function.

Python Program

iterable = [('m', 4), ('p', 8)]
myDictionary = dict(iterable, a=1, b=3, c=5)
print(myDictionary)

Output

{'m': 4, 'p': 8, 'a': 1, 'b': 3, 'c': 5}

If dict() cannot create dictionary from the iterable, the dict() function throws TypeError.

Python Program

iterable = [4, 8]
myDictionary = dict(iterable, a=1, b=3, c=5)
print(myDictionary)

Output

Traceback (most recent call last):
  File "d:/workspace/python/example.py", line 2, in <module>
    myDictionary = dict(iterable, a=1, b=3, c=5)
TypeError: cannot convert dictionary update sequence element #0 to a sequence

4 dict Empty Dictionary

In this example, we will not pass any values as arguments to dict() function. dict() returns an empty dictionary.

Python Program

myDictionary = dict()
print(myDictionary)

Output

{}

Conclusion

In this Python Tutorial, we have learnt the syntax of Python dict() builtin function, and also learned how to use this function, with the help of Python example programs.