Comments in Python

What are the Comments in Python?

       In Python, comments are notes written in the code to explain what the code does. They are ignored by Python when the program runs, meaning they don’t affect the code.

Comments are used to make the code more readable and to explain what specific parts of the code do. They are ignored by the Python interpreter when the program is run, which means they don't affect the execution of the program.

There are two types of comments in Python:

1. Single-line comments:
2. Multi-line comments:

1) Single-line comments: These comments begin with a # symbol. Anything after the # on that line will be treated as a comment.

Example:

# This is a single-line comment
print("Welcome to theagleye")  # This prints a message

 

2) Multi-line comments: Python doesn’t have an official multi-line comment syntax like some other languages. However, you can use triple quotes (''' or """) to write multi-line comments. These are actually treated as string literals but can serve as comments when not assigned to a variable. This Comment is also called a Document Interlude in Python.

 Example:

'''
This is a comment
on multiple lines.
'''
print("Hello")

"""
this is also a multiline Comment
the eagle eye
"""

---

20+ questions about Python comments, with answers and examples

Question 1. What are comments in Python?

Answer: Comments in Python are used to explain the code or to prevent code execution. They are ignored by the Python interpreter.

Example:

 

# This is a single-line comment
print("Hello, World!")

Output:

Hello, World!

 

Question 2. Why are comments used in Python?

Answer:

• To make code more readable.
• To explain complex logic or functionality.
• To temporarily disable code during debugging.

 

Question 3. How do you write a single-line comment in Python?

Answer: Use the # symbol at the beginning of the comment.

Example:

# This is a single-line comment
print("Python is fun!")

Output:

Python is fun!

 

Question 4. How do you write a multi-line comment in Python?

Answer: Use triple quotes (''' or """). Technically, they are string literals not assigned to variables but often used as comments.

Example:

"""
This is a multi-line comment.
It spans multiple lines.
"""
print("Multi-line comments are useful!")

Output:

Multi-line comments are useful!

 

Question 5. Can you write an inline comment in Python?

Answer: Yes, an inline comment is placed on the same line as a code statement.

Example:

x = 10  # This is an inline comment
print(x)  # Printing the value of x

Output:

10

 

Question 6. Does Python support block comments like other languages?

Answer: Python doesn't have a specific syntax for block comments. Instead, developers use multiple single-line comments or triple quotes.

 

Question 7. What happens if a comment is added after code without proper spacing?

Answer: There must be at least one space between the code and the # symbol to write a valid comment.

Example:

print("Hello, World!")#Invalid comment
print("Hello, World!") # Valid comment

 

Question 8. Are comments mandatory in Python code?

Answer: No, comments are not mandatory, but they are highly recommended to make code more understandable.

 

Question 9. Do comments affect the performance of Python programs?

Answer: No, comments are ignored by the Python interpreter and do not affect the performance of the program.

 

Question 10. Can you use a comment inside a string in Python?

Answer: No, the # inside a string is treated as part of the string, not as a comment.

Example:

text = "This is not a # comment"
print(text) 

Output:

This is not a # comment

 

Question 11. Can you use comments in Python to document a function or module?

Answer: Yes, docstrings (written using triple quotes) are used for documentation.

Example:

def add(a, b):
    """
    This function adds two numbers.
    """
    return a + b
print(add(2, 3))

Output:

5

 

Question 12. Can you nest comments in Python?

Answer: No, Python does not support nested comments. Each # symbol starts a new comment.

 

Question 13. How do comments differ from docstrings in Python?

Answer:

• Comments: Use # or triple quotes and are ignored by the interpreter.
• Docstrings: Written with triple quotes and can be accessed using the __doc__ attribute.

Example:

def example():
    """
    This is a docstring.
    """
    pass
print(example.__doc__) 

Output:

This is a docstring.

 

Question 14. Can comments be used to debug Python code?

Answer: Yes, developers can comment out lines of code to temporarily disable their execution during debugging.

 

Question 15. How do IDEs handle comments in Python?

Answer: Most IDEs provide shortcuts (e.g., Ctrl+/) to quickly comment or uncomment lines of code.

 

Question 16. What is a good practice for writing comments in Python?

Answer:

• Write concise and meaningful comments.
• Avoid obvious comments like # Add two numbers for a + b.
• Use comments to explain why, not what.

 

Question 17. What tools help check for comment quality in Python?

Answer: Tools like pylint and flake8 can check for the presence and quality of comments in the code.

 

Question 18. How can you comment out multiple lines of code quickly?

Answer: Use triple quotes for temporary commenting or the Ctrl+/ shortcut in an IDE.

Example:

"""
print("This is line 1")
print("This is line 2")
"""

 

Question 19. What is the significance of comments in collaborative Python projects?

Answer: Comments ensure that other developers can understand the code's purpose and logic, improving collaboration and maintainability.

 

Question 20. What happens if a line starts with # in Python?

Answer: The entire line is ignored by the interpreter, regardless of its content.