How to solve Python error: IndentationError: expected an indented block?

How to solve the Python error: IndentationError: expected an indented block?

Python, as an easy-to-learn and easy-to-use programming language, is often used to develop various applications and solve problems. However, even experienced developers may encounter some common mistakes. One of them is IndentationError: expected an indented block (indentation error: expected an indented block).

In Python, indentation is very important. It is used to identify the beginning and end of a block of code. Python syntax stipulates that in control flow statements (such as if statements and loop statements) and function definitions, code blocks must be indented by a certain number of spaces. When we use incorrect indentation in these places, an IndentationError will result.

Below we will introduce several common IndentationError situations and provide corresponding solutions.

1. Wrong number of spaces
   In Python, four spaces are usually used for indentation. If you use other spaces or tabs for indentation, an IndentationError will occur. Here is an example:

def my_function():
print("Hello, world!")

In the above example, the my_function() function is not indented correctly. Solving this problem is very simple, just add four spaces before the print statement:

def my_function():
    print("Hello, world!")

2. Inconsistent indentation
   In Python, it is generally recommended to use spaces for indentation, and Not a tab character. If you use both spaces and tabs for indentation in the same block of code, an IndentationError will occur. Here is an example:

def my_function():
    print("Hello, world!")
        print("Welcome to Python!")

In the above example, the second print statement is indented using tabs instead of four spaces. To solve this problem, we need to replace the tab character with four spaces before the second print statement:

def my_function():
    print("Hello, world!")
    print("Welcome to Python!")

3. Indent the wrong statement
   Sometimes, in the code, it may An incorrectly indented statement occurs. This means that the beginning and end of the code block are not correctly identified. Here is an example:

if 5 > 3:
    print("Five is greater than three!")
print("Hello, world!")

In the above example, the second print statement is indented incorrectly. It was mistakenly placed outside the if statement. In order to solve this problem, we need to adjust the indentation of the second print statement to the same indentation as the if statement:

if 5 > 3:
    print("Five is greater than three!")
    print("Hello, world!")

To summarize, to solve the IndentationError: expected an indented block error, we need to pay attention to the following A few points:

1. Use four spaces for indentation.
2. Avoid mixing spaces and tabs for indentation in the same code block.
3. Make sure the beginning and end of your code block are properly indented.

By following these rules, we can avoid the occurrence of IndentationError errors and write standardized and readable Python code.

I hope this article will help you solve the IndentationError error!

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