# Python Definitions

Python, being a dynamically typed language, offers a variety of value types (data types) and keywords that are integral to its programming structure. Here's a list of some common value types and keywords along with their definitions:

### Value Types (Data Types)

1. **`int`**: Represents integer values. Example: `5`, `-3`.
2. **`float`**: Represents floating-point numbers (decimals). Example: `3.14`, `-0.001`.
3. **`str`**: String type for text. Example: `"Hello"`, `'Python'`.
4. **`bool`**: Boolean type, representing `True` or `False`.
5. **`list`**: An ordered, mutable (changeable) collection of items. Example: `[1, 2, 3]`, `['a', 'b', 'c']`.
6. **`tuple`**: An ordered, immutable collection of items. Example: `(1, 2, 3)`, `('a', 'b', 'c')`.
7. **`dict`**: Dictionary type, an unordered collection of key-value pairs. Example: `{'name': 'Alice', 'age': 25}`.
8. **`set`**: An unordered collection of unique items. Example: `{1, 2, 3}`.
9. **`NoneType`**: Special type representing the absence of a value or a null value. Example: `None`.

### Keywords

1. **`def`**: Used to define a function. Example: `def my_function():`.
2. **`return`**: Used to return a value from a function.
3. **`class`**: Used to define a class.
4. **`import`**, **`from`**: Used to import modules or specific functions, classes, etc., from modules.
5. **`as`**: Used in import statements to give an imported module a different alias, or with `try...except` blocks to rename exceptions.
6. **`if`**, **`elif`**, **`else`**: Conditional statements.
7. **`for`**, **`while`**: Loop control statements.
8. **`break`**: Exits a loop.
9. **`continue`**: Skips the current iteration in a loop.
10. **`try`**, **`except`**, **`finally`**, **`raise`**: Exception handling keywords.
11. **`with`**: Used for exception handling in resource management (like file reading/writing).
12. **`global`**: Declares a variable as global.
13. **`nonlocal`**: Declares a variable as non-local (useful in nested functions).
14. **`lambda`**: Used to create an anonymous function.
15. **`yield`**: Used in a function like `return`, but for generator functions.
16. **`del`**: Deletes an object.
17. **`pass`**: A null statement, a placeholder for future code.
18. **`assert`**: Used for debugging purposes to check conditions that should always be `True`.
19. **`in`**, **`not in`**: Membership operators.
20. **`is`**, **`is not`**: Identity operators.