Introduction: Python help() Function
When working with Python, you may need quick information about functions, modules, classes, or objects while writing code. Access to documentation helps you understand features, syntax, and usage without interrupting the development process.
Without a direct way to view documentation, you would need to search external resources or check references manually, making learning and debugging slower.
This is where the Python help() Function provides a solution.
What it is: The help() function is a built-in Python function that provides documentation, syntax details and usage information for modules, classes, functions, methods and objects through Python’s interactive help system.
Take a look at a quick example to see how the help() function works.
You can also explore its real-world use cases to understand its practical applications.
Now let’s explore the syntax, parameters, return value, and practical examples to understand how the help() function works in Python.
💡 Tip: Continue your Python learning journey by exploring the Python Built-in Functions Learning Guide for detailed tutorials, syntax explanations, and practical examples.
Syntax, Parameters, Return Value and Examples: Python help() Function
The following section explains the syntax, parameters, return value, and a quick example of the Python help() Function.
Syntax
help()
help(object)Parameters
| Parameter | Description |
|---|---|
object (optional) |
The object whose documentation needs to be displayed. It can be a module, class, function, method, or any Python object. |
Return Value
| Return Value | Description |
|---|---|
| None | The help() function displays documentation and does not return a value. |
Quick Example
The following example displays documentation information about the print() function using the help() function.
help(print)
# Output:
Help on built-in function print in module builtins:
print(...)
Prints the values to a stream, or to sys.stdout.
The help() function displays the available documentation for print(), including its purpose and usage details.
How the Python help() function works
- The
help()function accepts a Python object as an optional argument. - It searches for available documentation related to the specified object.
- It displays information about functions, classes, modules, and methods.
- If no argument is provided, it opens Python’s interactive help system.
- It is commonly used while learning, exploring, and debugging Python programs.
- The function displays information without modifying the original object.
Examples: Python help() Function
The following examples show how the Python help() Function works in different programming scenarios.
Example 1: Using help() with a Built-in Function
help(len)
# Output:
Help on built-in function len:
len(obj, /)
Return the number of items in an object.
Explanation: The help() function displays documentation about the built-in len() function, including its purpose and usage.
Example 2: Using help() with a String Method
help(str.upper)
# Output:
Help on method_descriptor:
upper(self, /)
Return a copy of the string converted to uppercase.
Explanation: The help() function provides information about the upper() method available for string objects.
Example 3: Using help() with a Module
import math
help(math)
# Output:
Help on module math:
Contains mathematical functions.
Explanation: The help() function displays documentation related to the imported module and its available features.
Example 4: Using help() with a User-defined Function
def greet():
"""
Displays a greeting message.
"""
print("Hello")
help(greet)
# Output:
Help on function greet:
Displays a greeting message.
Explanation: The documentation string (docstring) of the user-defined function is displayed by the help() function.
Example 5: Using help() Without an Argument
help()
# Output:
Welcome to Python help utility.
Explanation: When used without an argument, the help() function starts Python’s interactive help system.
Example 6: Using help() to Understand a Class
class Student:
"""
Represents student information.
"""
pass
help(Student)
# Output:
Help on class Student:
Represents student information.
Explanation: The help() function displays available documentation and information about the user-defined class.
Use Cases: When to use the help() Function
Below are some common situations where the Python help() Function becomes useful:
- Learning the usage of built-in functions and methods.
- Understanding syntax and documentation of Python objects.
- Exploring unfamiliar modules and libraries.
- Checking available information about classes and functions.
- Reading documentation while developing programs.
- Debugging code by understanding object functionality.
Key Takeaways: help() Function
Before wrapping up, here are the key points to remember about the Python help() Function:
- The
help()function displays documentation about Python objects. - It can provide information about functions, methods, classes, and modules.
- It opens the interactive help system when used without an argument.
- It is useful for learning and exploring Python functionality.
- The function displays information without modifying objects.
- It helps developers understand Python features directly from the interpreter.
In short, the Python help() Function provides quick access to Python documentation, making it easier to learn, explore, and work with different programming features.