Get first key in dictionary python – Get first key-value pair from a Python Dictionary

August 18, 2022August 18, 2022 by Satyabrata Jena

Finding first key-value pair from a Dictionary in Python

Get first key in dictionary python: In this article, we will see of different methods by which we can fetch the first key-value pair of a dictionary. We will also discuss how to get first N pairs and any number of key-value pairs from a dictionary.

Getting first key-value pair of dictionary in python using iter() & next() :

In python, iter() function creates a iterator object of the the iterable sequence of key-value pairs from dictionary and by calling next() function we can get the first key-value pair.

# Program :

dict_eg = {
    'Sachin' : 10,
    "Gayle"  : 333,
    'Kohil'  : 18,
    'Murali' : 800,
    'Dhoni'  : 7,
    'AB'     : 17
}
# Get the first key-value pair in dictionary
dict_eg = next(iter((dict_eg.items())) )
print('The first Key Value Pair in the Dictionary is:')
print(dict_eg)
print('First Key: ', dict_eg[0])
print('First Value: ', dict_eg[1])

Output :
The first Key Value Pair in the Dictionary is:
('Sachin', 10)
First Key:  Sachin
First Value:  10

Get first key-value pair of dictionary using list :

In python, items() function in dictionary returns the iterable sequence of all key-value pairs. Then by creating a list from all key-value pairs in dictionary and by selecting the first item we will get first key-value pair of dictionary.

# Program :

dict_eg = {
    'Sachin' : 10,
    "Gayle"  : 333,
    'Kohil'  : 18,
    'Murali' : 800,
    'Dhoni'  : 7,
    'AB'     : 17
}
# Get the first key-value pair in dictionary
dict_eg = list(dict_eg.items())[0]
print('First Key Value Pair of Dictionary:')
print(dict_eg)
print('Key: ', dict_eg[0])
print('Value: ', dict_eg[1])

Output :
First Key Value Pair of Dictionary:
('Sachin', 10)
Key:  Sachin
Value:  10

Getting the first N key-value pair of dictionary in python using list & slicing :

Here from similar process, we will create a list of key-value pairs from dictionary. We can get first ‘N’ items by list[:N] or any items by list[start:end].

# Program :

dict_eg = {
    'Sachin' : 10,
    "Gayle"  : 333,
    'AB'     : 17,
    'Murali' : 800,
    'Dhoni'  : 7,
    'AB'     : 17,
    'Kohil'  : 18
}
n = 5
# Get first 5 pairs of key-value pairs
firstN_pairs = list(dict_eg.items())[:n]
print('The first 5 Key Value Pairs of Dictionary are:')
for key,value in firstN_pairs:
    print(key, '::', value)

Output :
The first 5 Key Value Pairs of Dictionary are:
Dhoni :: 7
Kohil :: 18
Gayle :: 333
Sachin :: 10
AB :: 17

Getting the first N key-value pair of dictionary in python using itertools :

We can slice first ‘N’ entries from a sequence by itertools.islice(iterable, stop) after creating key-value pairs sequence from items() function.

# Program :

import itertools
dict_eg = {
    'Sachin' : 10,
    "Gayle"  : 333,
    'AB'     : 17,
    'Murali' : 800,
    'Dhoni'  : 7,
    'AB'     : 17,
    'Kohil'  : 18
}
n = 5
# Get first 5 pairs of key-value pairs
firstN_pairs = itertools.islice(dict_eg.items(), n)
print('The first 5 Key Value Pairs of Dictionary are:')
for key,value in firstN_pairs:
    print(key, '::', value)

Output :
The first 5 Key Value Pairs of Dictionary are:
Murali :: 800
AB :: 17
Sachin :: 10
Dhoni :: 7
Kohil :: 18

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