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Sugam Adhikari
Sugam Adhikari

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Python Coding Best Practices for Beginners

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Introduction

Writing clean and maintainable code is essential for effective programming...View

1. Code Readability

  • Use meaningful variable and function names
  • Follow consistent indentation
  • Keep lines of code short
  • Use whitespace wisely

2. Naming Conventions

  • Use of snake_case
  • Use of UPPERCASE
  • Use of CamelCase

3. Commenting

  • Add comments to explain complex logic or non-obvious code sections
  • Use inline comments sparingly

4. Code Organization

  • Use whitespace and blank lines to separate logical sections of your code
  • Group related functions together
  • Break down large functions into smaller, more manageable functions with specific purposes
  • Use modules and packages to organize and encapsulate related code
  • Import modules at the top of your file to maintain clarity
  • Follow the principle of "Don't Repeat Yourself" (DRY) by reusing code through functions and classes

Conclusion

Following these coding best practices will help you write clean, readable, and maintainable Python code...View


Introduction:

Writing clean and maintainable code is essential for effective programming. In this guide, we will explore fundamental coding best practices to follow when writing Python code. These practices focus on code readability, naming conventions, commenting, and code organization. By adhering to these best practices, you can improve the quality of your code and make it easier to understand and maintain.


1. Code Readability

Writing code that is easy to read and understand is crucial for collaboration and maintenance.

  • Use meaningful variable and function names:
# Bad example:
x = 5  # What does 'x' represent?

# Good example:
num_items = 5  # Descriptive variable name
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  • Follow consistent indentation:
# Bad example:
for i in range(5):
print(i)  # Inconsistent indentation

# Good example:
for i in range(5):
    print(i)  # Consistent indentation
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  • Keep lines of code short:
# Bad example:
result = calculate_some_long_expression_with_many_operations(argument1, argument2, argument3, argument4)

# Good example:
result = calculate_some_long_expression_with_many_operations(
    argument1, argument2, argument3, argument4
)
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  • Use whitespace wisely:
# Bad example:
result=a+b*c/d  # Lack of whitespace

# Good example:
result = a + b * c / d  # Improved readability with whitespace
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2. Naming Conventions:

Consistent naming conventions make your code more readable and understandable.

  • snake_case: Snake case involves writing all lowercase letters with underscores (_) to separate words. It's commonly used for naming variables and functions.
# Bad example:
MyVariable = 5  # Inconsistent naming convention

# Good example:
my_variable = 5  # Consistent naming convention
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  • Uppercase: Uppercase is used for constants, which are variables with values that remain unchanged throughout the program's execution.
# Bad example:
pi = 3.14  # Not clear that it's a constant

# Good example:
PI = 3.14  # Clear indication of a constant
MAX_ATTEMPTS = 5 # You can add underscore as well
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  • CamelCase: In Python community, people often say "CamelCase" for all capitalization styles, but it's more accurate to call it "PascalCase."
# Bad example:
class myclass:
    #code...
my_class = myclass()  # Class name should be in CamelCase

# Good example:
class MyClass:
    #code...
my_class = MyClass()  # Correct usage of CamelCase
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3. Commenting:

Comments provide additional explanations and make your code more understandable.

  • Add comments to explain complex logic or non-obvious code sections:
# Bad example: Unclear variable names and lack of explanation.

x = a * b - c / d  # Complex mathematical operation

# Good example: Clear variable names and explanation of the operation.

# Calculate the product of 'a' and 'b', subtract the result of 'c' divided by 'd'.
result = a * b - c / d
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  • Use inline comments sparingly:
# Bad example:
result = a + b  # Add 'a' and 'b' together
c = result * 2  # Multiply 'result' by 2

# Good example:
result = a + b  # Calculate the sum
c = result * 2  # Double the result
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4. Code Organization:

Well-organized code enhances readability and maintainability.

  • Use whitespace and blank lines to separate logical sections of your code:
# Bad example:
def calculate_area(length, width):
    area=length*width
    return area
def calculate_perimeter(length, width):
    # code...

# Good example:
def calculate_area(length, width):
    area = length * width #using whitespace
    return area

# Blank line for separation
def calculate_perimeter(length, width):
    # code...
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  • Group related functions together: It helps a lot when there is lots of function and you have to spot logic, find error or make changes in code.
# Bad example:
def calculate_area(length, width):
    # code...

def greet_user(name):
    # code...

def calculate_perimeter(length, width):
    # code...

# Good example:
# Group related functions together
# here area and perimeter functions are together.
def calculate_area(length, width):
    # code...

def calculate_perimeter(length, width):
    # code...

def greet_user(name):
    # code...
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  • Break down large functions into smaller, more manageable functions with specific purposes:
# Bad example:
def process_data(data):
    # 100 lines of code...

# Good example:
def process_data(data):
    preprocess_data(data)
    analyze_data(data)
    visualize_data(data)

def preprocess_data(data):
    # code...

def analyze_data(data):
    # code...

def visualize_data(data):
    # code...
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  • Use modules and packages to organize and encapsulate related code.

  • Import modules at the top of your file to maintain clarity.

# Bad example: In this example you can't use this module again in another function and class unless you import again!

def my_function():
    import module_a
    result = module_a.some_function()
    # code...

def another_function():
    import module_a
    result = module_a.some_function()
    # code...

# Good example: Here you can use by importing only once!
import module_a

def my_function():
    result = module_a.some_function()
    # code...

def another_function():
    result = module_a.some_function()
    # code...
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  • Follow the principle of "Don't Repeat Yourself" (DRY) by reusing code through functions and classes:
# Bad example:
def calculate_area(length, width):
    # code...

def calculate_perimeter(length, width):
    # code...

def calculate_volume(length, width, height):
    area = length * width 
    return area * height

# Good example:
def calculate_area(length, width):
    # code...

def calculate_perimeter(length, width):
    # code...

def calculate_volume(length, width, height):
    area = calculate_area(length, width) #Use functions if available

    return area * height
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Conclusion:


Following these coding best practices will help you write clean, readable, and maintainable Python code. By prioritizing code readability, using consistent naming conventions, providing appropriate comments, and organizing your code effectively, you can improve collaboration, reduce bugs, and make your codebase more maintainable. Remember to practice these best practices consistently to develop good coding habits. Happy coding!

Please note that the code examples provided here are for illustrative purposes and may not cover all possible scenarios. Also note that, in small code these advantages may not be seen but when your codebase is huge it's effect can be seen more clearly. It's essential to adapt these best practices to the specific requirements of your projects and follow any coding standards established by your team or organization.

Top comments (2)

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taikedz profile image
Tai Kedzierski

Good summary of the basics of keeping code tidy 👍

I tend to throw about the idea that focusing on readability (incl functions and good names) is more important than focus on correctness : it's easier to see problems in readable code, but who knows if unreadable code is correct...

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testsuya profile image
Sugam Adhikari

Well, we just need to make sure later our code is understood not only by God but also us.🤭