This tutorial provides a comprehensive overview of Python keywords, which are essential building blocks in Python programming. Python keywords are reserved words with predefined meanings and functions, and they cannot be used for any other purpose in the code. Unlike built-in methods and classes, keywords have strict limitations on their usage. Using a keyword for anything other than its designated purpose will result in a SyntaxError.
Retrieve Keywords: You can list all keywords in your Python version using:
import keyword
print(keyword.kwlist)
To identify whether a word is a Python keyword, you can:
1. Use syntax highlighting in an IDE, where keywords are typically highlighted.
2. Write a small script in a REPL to check if a word is a keyword using keyword.iskeyword('word').
3. Look for a SyntaxError when trying to misuse a keyword.
• True and False: These represent the Boolean values in Python, used in comparisons and logical operations.
• None: Represents the absence of a value, often used as a default return value for functions that don't explicitly return anything.
• and: Returns True if both operands are true.
• or: Returns True if at least one operand is true.
• not: Inverts the Boolean value.
• in: Checks if an element is contained within a container (like a list or string).
• is: Checks if two references point to the same object in memory.
• nonlocal: Used within nested functions to modify variables in the outer (but not global) scope.
• for: Used for iterating over a sequence (like a list, tuple, dictionary, or string).
• while: Repeats a block of code as long as a condition is true.
• break: Exits a loop prematurely.
• continue: Skips the rest of the current loop iteration and moves to the next iteration.
• try and except: Used for handling exceptions (errors) in the code.
• raise: Explicitly raises an exception.
• finally: A block of code that runs regardless of whether an exception occurred.
• assert: Used for debugging, it tests a condition and raises an AssertionError if the condition is false.
• pass: A null statement used as a placeholder where code will eventually go.
• return: Used to exit a function and optionally pass back a value.
• del: Deletes objects, variables, or elements from a collection like a list or dictionary.