Gain insights into Python by exploring basic to advanced concepts, including loops, classes, and GUIs with Tkinter. Delve into testing and become a productive Python programmer.

complete.tar.gz

InputN-copy

Error-copy

In this course, you will get a comprehensive overview of Python. You will start by laying the foundation and learning the introductory topics like operators, conditional statements, functions, loops, assignment statements, and more. You will then move onto more advanced topics such as classes and inheritance, iterators, list comprehensions, and dictionaries. Along with this, you will also get to explore the concept of testing and take a look at how GUI applications can be designed using Tkinter, Python's standard GUI library. 

By the time you're done, you'll be able to hit the ground running and be equipped with the tools that will allow you to be productive in Python.

Python 3: From Beginner to Advanced

## Introduction to scope

The **scope** of a name is the part of the program in which the name has meaning and can be used. Python’s scope rules are unusual because they follow an “LEGB rule”: **L**ocal, **E**nclosed, **G**lobal, **B**uilt-in. 

To understand this rule, it helps to remember that:

1. Variables are **defined** by being **assigned a value**. 
2. Functions/methods may be **nested within other** functions/ methods.

When dealing with the scope of a variable in Python, keep in mind the following point:

- Variables may be declared **global** or **nonlocal** by a statement in the form `global var1,...,varN` or `nonlocal var1,...,varN`. The declaration must **precede** any use of the variable.

## Types of scopes

Following are four different types of scope present in Python:

- **Local**: A variable is **local** to a function if it is **assigned** a value **within that** function, and it is not declared otherwise.

- **Enclosed**: A variable in a function can refer to a variable declared in an enclosing function, provided either of the following conditions are met: 
  1) The variable is **not assigned** a value in this function.
  2) It is declared in a `nonlocal` statement.

- **Global**: A variable declared at the **top level** (not in a function or method) is **global**, and it can be referenced throughout the program. A variable in a function can refer to a global variable, provided either of the following conditions are met:
  1) The variable is **not assigned** a value in this function or in an enclosing function.
  2) It is **declared in a global** statement.

- **Built-in**: A variable not declared otherwise in the program might be a built-in variable. Some examples are `list`, `print`, and `divmod`.

# Introduction to scope

The **scope** of a name is the part of the program in which the name has meaning and can be used. Python’s scope rules are unusual because they follow an “LEGB rule”: **L**ocal, **E**nclosed, **G**lobal, **B**uilt-in. 

To understand this rule, it helps to remember that:

1. Variables are **defined** by being **assigned a value**. 
2. Functions/methods may be **nested within other** functions/ methods.

When dealing with the scope of a variable in Python, keep in mind the following point:

- Variables may be declared **global** or **nonlocal** by a statement in the form `global var1,...,varN` or `nonlocal var1,...,varN`. The declaration must **precede** any use of the variable.

# Types of scopes

Following are four different types of scope present in Python:

- **Local**: A variable is **local** to a function if it is **assigned** a value **within that** function, and it is not declared otherwise.

- **Enclosed**: A variable in a function can refer to a variable declared in an enclosing function, provided either of the following conditions are met: 
  1) The variable is **not assigned** a value in this function.
  2) It is declared in a `nonlocal` statement.

- **Global**: A variable declared at the **top level** (not in a function or method) is **global**, and it can be referenced throughout the program. A variable in a function can refer to a global variable, provided either of the following conditions are met:
  1) The variable is **not assigned** a value in this function or in an enclosing function.
  2) It is **declared in a global** statement.

- **Built-in**: A variable not declared otherwise in the program might be a built-in variable. Some examples are `list`, `print`, and `divmod`.

In this lesson, you'll learn about the scope of variables in Python.

Introduction

The Absolute Bare Minimum

Better Tools

Classes

Getting Fancy

Testing

Graphical User Interfaces

Modules

Appendix

I Guess We're Doing Python Now Exam

Scope

Introduction to scope