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Python Data Structures
course content

Course Content

Python Data Structures

Python Data Structures

1. Mastering Python Lists
Creating Lists in Python: Declaring and Initializing ListsList Indexing in Python: Accessing Elements EfficientlyWorking with Nested Lists in PythonPython List Length: Measuring and Managing List SizeModifying Lists in Python: Updating and Changing ElementsUsing the append() Method: Adding Elements to ListsUsing the insert() Method: Placing Elements at Specific PositionsDeleting Elements in Python Lists: Removing Items SafelyUsing the remove() Method: Deleting Specific Elements from Lists
2. Mastering Python Dictionaries
Creating a Dictionary in Python: Storing Key-Value PairsAccessing Dictionary ValuesAccessing Dictionary KeysAdding Items to a Dictionary: Updating Key-Value PairsUsing the del Keyword: Removing Dictionary EntriesUsing the pop() Method: Deleting Elements with Return ValuesUsing the popitem() Method: Removing the Last Inserted ItemUsing the clear() Method: Emptying a Dictionary Completely
3. Mastering Python Tuples
Creating a Tuple in Python: Defining Immutable Data StructuresAccessing Elements in a Tuple: Indexing TechniqueConcatenating Tuples in Python: Merging Immutable SequencesDeleting Tuples in Python: Removing References to TuplesUpdating Tuples in PythonAdding Items to a Tuple: Alternative Approaches Using ListsCounting Elements in a Tuple: Using the count() MethodFinding Elements in a Tuple: Using the index() Method for Lookup
4. Mastering Python Sets
Creating a Set in Python: Defining Unordered CollectionsUsing the add() Method: Adding Single Elements to a SetUsing the update() Method: Merging Multiple Elements into a SetAccessing Elements in a Set: Iteration and Membership TestingUsing the remove() and discard() MethodsUsing the clear() Method: Removing All Elements from a Set

book
Using the remove() and discard() Methods

Sets in Python allow you to remove elements using the remove() and discard() methods. While both methods remove specific elements, there is a key difference:

  • remove(): raises a KeyError if the element is not in the set;
  • discard(): does not raise an error if the element is not found; it simply leaves the set unchanged.

Let's explore these methods using a movie collection theme.


              
123456

            
# Attempting to remove movies
movies = {"Inception", "Interstellar", "Tenet", "Dunkirk"}

# Remove specific movies
movies.remove("Dunkirk")
movies.remove("Avatar")  # This will raise a `KeyError`
copy

Now, let's use the discard() method, which behaves similarly but avoids errors if the specified movie is not in the set.


              
12345678910

            
# Define a set of favorite movies
movies = {"Inception", "Interstellar", "Tenet", "Dunkirk", "Memento"}

# Remove specific movies using discard
movies.discard("Dunkirk")
movies.discard("Memento")
movies.discard("Avatar")

# Print the result
print("Final set:", movies)
copy
Task

Swipe to start coding

You are given the set marvel_movies. However, two movies from another studio have accidentally been added to this set.

Your goal:

  • Remove the movie "The Dark Knight" from the set.
  • Remove the movie "Justice League" from the set.
  • Use the discard() or remove() methods to accomplish this task.

Solution

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Section 4. Chapter 5
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book
Using the remove() and discard() Methods

Sets in Python allow you to remove elements using the remove() and discard() methods. While both methods remove specific elements, there is a key difference:

  • remove(): raises a KeyError if the element is not in the set;
  • discard(): does not raise an error if the element is not found; it simply leaves the set unchanged.

Let's explore these methods using a movie collection theme.


              
123456

            
# Attempting to remove movies
movies = {"Inception", "Interstellar", "Tenet", "Dunkirk"}

# Remove specific movies
movies.remove("Dunkirk")
movies.remove("Avatar")  # This will raise a `KeyError`
copy

Now, let's use the discard() method, which behaves similarly but avoids errors if the specified movie is not in the set.


              
12345678910

            
# Define a set of favorite movies
movies = {"Inception", "Interstellar", "Tenet", "Dunkirk", "Memento"}

# Remove specific movies using discard
movies.discard("Dunkirk")
movies.discard("Memento")
movies.discard("Avatar")

# Print the result
print("Final set:", movies)
copy
Task

Swipe to start coding

You are given the set marvel_movies. However, two movies from another studio have accidentally been added to this set.

Your goal:

  • Remove the movie "The Dark Knight" from the set.
  • Remove the movie "Justice League" from the set.
  • Use the discard() or remove() methods to accomplish this task.

Solution

Switch to desktopSwitch to desktop for real-world practiceContinue from where you are using one of the options below
Everything was clear?

How can we improve it?

Thanks for your feedback!

Section 4. Chapter 5
Switch to desktopSwitch to desktop for real-world practiceContinue from where you are using one of the options below
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