Python dict keys get first key

Get First Key and Value in Dictionary with Python

In Python, there are a few different ways we can get the first key/value pair of a dictionary. The easiest way is to use the items() function, convert it to a list, and access the first element.

dictionary = < "key1":"This", "key2":"is", "key3":"a", "key4":"dictionary." >first_item = list(dictionary.items())[0] print("The first item of the dictionary has key: " + first_item[0] + " and value: " + first_item[1]) #Output: The first item of the dictionary has key: key1 and value: This

Another way to get the first key and value in a dictionary is to convert it to a list and access the first element. This will get the first key, and then you can get the first value by accessing that key in the

dictionary = < "key1":"This", "key2":"is", "key3":"a", "key4":"dictionary." >first_key = list(dictionary)[0] print("The first key of the dictionary is: " + first_key) #Output: The first key of the dictionary is: key1

If you only care about getting the first value of a dictionary, you can use the dictionary values() function.

dictionary = < "key1":"This", "key2":"is", "key3":"a", "key4":"dictionary." >first_value = list(dictionary.values())[0] print("The first value of the dictionary is: " + first_value) #Output: The first value of the dictionary is: This

In Python, dictionaries are a collection of key/value pairs separated by commas. When working with dictionaries, it can be useful to be able to easily access certain elements.

We can easily get the first item from a dictionary and get the first key and first value.

The easiest way to get the first item from a dictionary is with the items() function. The items() function returns a dict_items object, but we can convert it to a list to easily and then access the first element like we would get the first item in a list.

Below is an example of how you can use the dictionary items() function to get the first item of a dictionary.

dictionary = < "key1":"This", "key2":"is", "key3":"a", "key4":"dictionary." >first_item = list(dictionary.items())[0] print(first_item) print("The first item of the dictionary has key: " + first_item[0] + " and value: " + first_item[1]) #Output: ('key1','This') The first item of the dictionary has key: key1 and value: This

Get First Key in Dictionary Using Python

The example above is great for getting the first item in a dictionary. If you only care about getting the first key, there are a few ways you can get the first key of a dictionary.

You can use the Python dictionary keys() function, convert it to a list, and access the first element, or just convert the dictionary to a list and then access the first element.

Below shows two different ways to get the first key from a dictionary in Python.

dictionary = < "key1":"This", "key2":"is", "key3":"a", "key4":"dictionary." >first_key = list(dictionary)[0] print("The first key of the dictionary is: " + first_key) first_key = list(dictionary.keys())[0] print("The first key of the dictionary is: " + first_key) #Output: The first key of the dictionary is: key1 The first key of the dictionary is: key1

Get First Value in Dictionary Using Python

If you only care about getting the first value, there are a few ways you can get the first value of a dictionary.

To get the first value in a dictionary, you can use the Python dictionary values() function, convert it to a list, and access the first element.

Below shows two different ways to get the first value from a dictionary in Python.

dictionary = < "key1":"This", "key2":"is", "key3":"a", "key4":"dictionary." >first_value = list(dictionary.values())[0] print("The first value of the dictionary is: " + first_value) #Output: The first value of the dictionary is: This

Get the First n Items in Dictionary Using Python

We can use the items() function to get the first n items in a dictionary using Python. Since we convert the dict_items object to a list, we can use slicing just like with lists to get the first n key/value pairs in a dictionary.

Below is an example of how you can use Python to get the first 3 items in a dictionary.

dictionary = < "key1":"This", "key2":"is", "key3":"a", "key4":"dictionary." >dict_items_list = list(dictionary.items())[0:3] for x in dict_items_list: print(x) #Output: ('key1', 'This') ('key2', 'is') ('key3', 'a')

Get the Last Item in Dictionary Using Python

Finally, if you want to get the last item in a dictionary, or get the last key and last value, you can use a very similar method as described above.

Now, instead of getting the first element, we get the last item from the list.

Below is an example in Python of how to get the last key and last value in a dictionary.

dictionary = < "key1":"This", "key2":"is", "key3":"a", "key4":"dictionary." >last_item = list(dictionary.items())[-1] print("The first item of the dictionary has key: " + last_item[0] + " and value: " + last_item[1]) #Output: The first item of the dictionary has key: key4 and value: dictionary.

Hopefully this article has been useful for you to understand how to get the first item from a dictionary in Python.

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How to get first key in Dictionary – Python

In this article we will discuss different ways to fetch the first key of a dictionary. Then we will look how to select first N keys of a dictionary in python.

Get first key from a dictionary using keys() method

In python, dictionary is a kind of container that stores the items in key-value pairs. It also provides a function keys(), that returns an iterable sequence of all keys in the dictionary. We will use that to fetch all keys in the dictionary and then we will select first key from that sequence i.e.

# Dictionary of string and int word_freq = < 'Hello': 56, "at": 23, 'test': 43, 'This': 78, 'Why': 11 ># Get the first key in a dictionary first_key = list(word_freq.keys())[0] print('First Key of dictionary:') print(first_key)

First Key of dictionary: Hello

Here we converted the iterable sequence of keys to a list and then selected the first element from the list i.e. first key of the dictionary

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If we try to convert dictionary to list by passing the dictionary object to list constructor list(), then implicitly it will convert all keys of the dictionary to list and then we can select the first element from the list i.e. first key of the dictionary,

# Dictionary of string and int word_freq = < 'Hello': 56, "at": 23, 'test': 43, 'This': 78, 'Why': 11 ># Get the first ket in a dictionary first_key = list(word_freq)[0] print('First Key of dictionary:') print(first_key)

First Key of dictionary: Hello

Here we didn’t even called the keys() function. We just created a list of keys from the dictionary and selected first item from it.

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Get first key in a dictionary using iter() & next()

In in the above solution, we created a list of all the keys and then selected the first key. It was not an efficient solution, because if our dictionary is large and we need only the first key, then why are we creating a huge list of all keys. As keys() returns an iterable sequence of dictionary keys, so we can create an iterator object of this iterable sequence of keys using iter() function. Then by calling the next() function on iterator object, we can get the first element of this sequence i.e. first key of the dictionary. For example,

# Dictionary of string and int word_freq = < 'Hello': 56, "at": 23, 'test': 43, 'This': 78, 'Why': 11 ># Get the first ket in a dictionary first_key = next(iter(word_freq)) print('First Key of dictionary:') print(first_key)

First Key of dictionary: Hello

This is an efficient solution because didn’t iterated over all the keys in dictionary, we just selected the first one.

Get first N keys from a Dictionary in Python

To select first N keys from a dictionary, convert the keys of a dictionary to a list and then select first N entries from that. For example, let’s see how to select first 3 keys from a dictionary,

# Dictionary of string and int word_freq = < 'Hello': 56, "at": 23, 'test': 43, 'This': 78, 'Why': 11 ># get list of first 3 keys from the dictionary n = 3 first_n_keys = list(word_freq.keys())[:n] print(f'First keys in the dictionary:') print(first_key)

First 3 keys in the dictionary: Hello

We learned about different about different ways to select first key from a dictionary in python.

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