Accessing Items in Python Dictionaries

1. Accessing Values with Keys:

# Use square brackets [] and the key to access the corresponding value
person = {'name': 'John', 'age': 30, 'city': 'New York'}
name = person['name']  # 'John'
age = person['age']    # 30

2. Using the get() Method:

# The get() method allows you to retrieve the value associated with a key. If the key is not present, it returns a default value (or None if no default is provided)
person = {'name': 'John', 'age': 30, 'city': 'New York'}
name = person.get('name')       # 'John'
occupation = person.get('job')  # Returns None

3. Accessing Keys, Values, and Items:

# You can use the keys(), values(), and items() methods to get lists of keys, values, and key-value pairs (as tuples), respectively
person = {'name': 'John', 'age': 30, 'city': 'New York'}
keys_list = person.keys()        # ['name', 'age', 'city']
values_list = person.values()    # ['John', 30, 'New York']
items_list = person.items()      # [('name', 'John'), ('age', 30), ('city', 'New York')]

4. Handling Missing Keys:

# You can use a combination of in and not in to check if a key is present in the dictionary before accessing its value
person = {'name': 'John', 'age': 30, 'city': 'New York'}
if 'name' in person:
    name = person['name']  # Access the value if the key is present
else:
    name = 'Unknown'

# Alternatively, you can use the get() method with a default value
person = {'name': 'John', 'age': 30, 'city': 'New York'}
name = person.get('name', 'Unknown')

These methods provide flexibility in accessing values from dictionaries, and you can choose the one that best suits your needs. Keep in mind that attempting to access a key that doesn't exist in the dictionary using square brackets will raise a KeyError. Using get() with a default value or checking for key existence helps handle such cases more gracefully.