How to Get Keys From Dictionary in Python

1. Introduction

In Python, dictionaries are used to store data as key-value pairs. Keys are a central concept in Python dictionaries, as they are unique identifiers used to retrieve the associated values. Understanding how to work with dictionary keys is crucial for effective dictionary manipulation.

Definition

The keys in a dictionary are the elements used to index and access the value pairs. In Python, dictionary keys must be immutable, such as strings, numbers, or tuples.

2. Program Steps

1. Create a dictionary with some key-value pairs.

2. Use the keys() method to retrieve the keys from the dictionary.

3. Iterate over the keys and print them.

4. Convert the keys view to a list and display it.

3. Code Program

# Step 1: Create a dictionary
my_dict = {'name': 'Ramesh', 'age': 25, 'location': 'Pune'}

# Step 2: Retrieve the keys using the keys() method
dict_keys = my_dict.keys()

# Step 3: Print the dictionary keys by iterating over them
print("Dictionary keys:")
for key in dict_keys:
    print(key)

# Step 4: Convert the keys to a list and print
keys_list = list(dict_keys)
print(f"List of dictionary keys: {keys_list}")

Output:

Dictionary keys:
name
age
location
List of dictionary keys: ['name', 'age', 'location']

Explanation:

1. my_dict is a dictionary that contains three key-value pairs.

2. dict_keys is a view of the keys in my_dict, obtained by calling my_dict.keys().

3. A for loop iterates over dict_keys, printing each key.

4. keys_list is created by casting dict_keys to a list, which can be useful for operations that require list data types.

5. print statements output the dictionary keys and the list of keys, demonstrating two ways to access and work with dictionary keys in Python.